Patent Description:
A battery module may include a plurality of battery cells stacked in one direction and having electrode leads electrically connected in series and/or in parallel, and a battery module housing for packaging the battery cells.

The battery module housing provides a mechanical support for the battery cells with insufficient mechanical stiffness and serves as a case for protecting the battery cells against external shocks. The battery module housing may be manufactured in various shapes depending on the battery module, and recently is frequently manufactured in a rectangular tube shape, which is referred to as a mono frame.

The conventional mono frame may be integrally manufactured by extrusion or die casting, or may be manufactured by joining four plates by welding.

However, if a problem occurs at an internal component of the battery module, for example battery cells or a thermistor interposed between the battery cells to measure the temperature of the cells, since the conventional battery module housing is integrally formed or manufactured by welding, the conventional battery module housing is not easily disassembled, and thus it is very difficult to repair or replace only the component with a problem.

Moreover, in the conventional battery module, if it is not possible to repair or replace the problem with a problem due to the above structure of the battery module housing, the remaining components that are normally working may not be reused and should be entirely discarded.

Meanwhile, the battery module housing may also be manufactured by coupling four plates in a snap-fitting manner so that the battery module housing may be reworked. However, the snap-fitting method is not a satisfactory alternative because the coupling portion may be easily damaged even by a small impact and also the sealing property is relatively low compared with the integral-type or welding-type battery module housing. Thus, it is necessary to develop a battery module housing with a new structure which is easy to rework and has advantages of the integral type and the welding type.

Documents <CIT>, <CIT> and <CIT> constitute prior art.

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 housing, which has high airtightness and is easy to rework when necessary, and a battery module including the battery module housing.

However, the objects of the present disclosure are not limited to the above, and objects not mentioned herein may be clearly understood from the present specification by those skilled in the art.

In one aspect of the present disclosure, there is provided a battery module housing, which includes a top plate and a bottom plate forming an upper wall and a lower wall, and a first side plate and a second side plate forming both side walls, the battery module housing having a rectangular tube shape provided to accommodate battery cells in an inner space thereof,
wherein the battery module housing has bonding portions formed by applying an adhesive along a longitudinal direction to four sites corresponding to sites between both side edges of the top plate opposite to each other and top surfaces of the first side plate and second side plate and sites between both side edges of the bottom plate opposite to each other and bottom surfaces of the first side plate and second side plate.

The bonding portion has a detachable jig insertion space formed at a predetermined location, and the adhesive is not applied to the detachable jig insertion space.

The detachable jig insertion space may be provided in plural, and the plurality of detachable jig insertion spaces may be intermittently formed along the longitudinal direction of the first side plate and the second side plate.

At least one of the first side plate and the second side plate may have a space expansion portion prepared by concavely forming a region corresponding to the detachable jig insertion space to have an uneven structure.

The battery module housing may further comprise insulation pads respectively attached to inner surfaces of the top plate, the first side plate and the second side plate; and a thermal transfer pad attached to an inner surface of the bottom plate.

The battery module housing may further comprise a caulking member filled in the detachable jig insertion space and made of a soft material.

The bonding portion of at least one of the four sites may be inclined toward the inner space at a predetermined angle.

At least one of the top plate and the bottom plate may have bent portions bent from both edges thereof and disposed in contact with outer side surfaces of the first side plate and the second side plate.

In another aspect of the present disclosure, there is also provided a battery module, which comprises the battery module housing described above.

According to an embodiment of the present disclosure, there is provided a battery module housing which is easy to rework, and thus if a problem occurs at an internal component of a battery module, it is possible to repair and replace the corresponding component and reuse the remaining components.

According to another embodiment of the present disclosure, the battery module housing is not only easy to rework but also gives airtightness as in the existing welding type.

Hereinafter, battery module housings which are not claimed and preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

<FIG> is a perspective view schematically showing a battery module housing not claimed in the present disclosure, but useful for emphasizing specific aspects of the claimed disclosure and battery cells accommodated therein, <FIG> is an exploded perspective view showing that a top plate is detached from the battery module housing of <FIG>, <FIG> is a schematic cross-sectioned view, taken along the line I-I' of <FIG>, <FIG> is a perspective view showing the battery module housing not claimed in the present disclosure, and <FIG> is an enlarged view showing a portion A of <FIG>.

A battery module housing <NUM> described below may be understood as a component such as a case for accommodating battery cells <NUM>. Here, the battery cells <NUM> may be pouch-type secondary batteries. The pouch-type secondary batteries may be stacked horizontally or arranged in multiple layers, and then accommodated in the inner space S of the battery module housing <NUM>. Although not shown in detail, other components such as a stacking frame for guiding the battery cells <NUM> to be stacked, a thermistor, and the like may be accommodated together in addition to the battery cells <NUM>.

Referring to <FIG>, the battery module housing <NUM> not claimed in the present disclosure is provided in a rectangular tube shape and include a top plate <NUM> and a bottom plate <NUM> forming an upper wall and a lower wall, and a first side plate <NUM> and a second side plate <NUM> forming both side walls.

The battery module housing <NUM> provides a mechanical support for the battery cells <NUM> and protect the battery cells <NUM> from external impacts. Thus, the four plates of the battery module housing <NUM> are preferably made of a metal material to secure rigidity.

Though not shown, an interconnection board (ICB) assembly for connecting the battery cells <NUM> in series and/or in parallel is coupled to the front surface and the rear surface of the battery module housing <NUM>. The ICB assembly includes a plurality of bus bars and an ICB housing capable of covering the front surface and the rear surface of the battery module housing <NUM>. For reference, as shown in <FIG>, the electrode leads <NUM> of the battery cells <NUM> exposed on the front surface and the rear surface of the battery module housing <NUM> are welded to the bus bars to electrically connected and covered with the ICB housing, respectively.

The first side plate <NUM> and the second side plate <NUM> of the battery module housing <NUM> have the same thickness and the same shape, and the top plate <NUM> and the bottom plate <NUM> also have the same thickness and the same shape. At this time, the thickness of the first side plate <NUM> and the second side plate <NUM> is relatively thicker than the thickness of the top plate <NUM> and the bottom plate <NUM> for the robustness of the battery module housing <NUM>.

In particular, the battery module housing <NUM> according to <FIG> are manufactured in an adhesive manner so that the four plates <NUM>, <NUM>, <NUM>, <NUM> may be partially disassembled, unlike the conventional welding method.

Specifically, as shown in <FIG>, the battery module housing <NUM> has bonding portions <NUM> at for spots. The bonding portions <NUM> are formed as the adhesive <NUM> is applied along the longitudinal direction (the X-axis direction) at four spots corresponding to spots between both side edges of the top plate <NUM> opposite to each other and the top surfaces of the first side plate <NUM> and the second side plate <NUM> and spots between both side edges of the bottom plate <NUM> opposite to each other and the bottom surfaces of the first side plate <NUM> and the second side plate <NUM>.

The disassembling operation of the battery module housing <NUM> will be described briefly. Generally, the bonding strength of the adhesive <NUM> may be lowered to about <NUM> to <NUM>% compared to the ordinary state under normal temperature and humidity conditions. Thus, the disassembling work of the battery module housing <NUM> is performed in a state where the bonding performance is sufficiently low after the pretreatment process such as storing the battery module in a hot and humid space for a predetermined time or locally applying heat and/or moisture around the bonding portion <NUM>.

Meanwhile, the battery module housing <NUM> further includes an insulation pad <NUM> for preventing the heat from being transmitted to the battery cells <NUM> when heat is locally applied around the bonding portion <NUM> to weaken the performance of the adhesive <NUM> of the corresponding bonding portion <NUM>.

For example, as shown in <FIG>, the insulation pad <NUM> is attached to the inner surface of each of the top plate <NUM>, the first side plate <NUM> and the second side plate <NUM>. According to this configuration, even if heat is applied to the top plate <NUM>, the first side plate <NUM> and the second side plate <NUM> during the pretreatment process for disassembling the battery module housing <NUM>, the battery cells <NUM> is protected from external heat.

In addition, a thermal transfer pad <NUM> is attached to the bottom plate <NUM>. As shown in <FIG>, even if heat is applied to the upper portion of the battery module housing <NUM> and transferred to the battery cells <NUM>, the temperature of the battery cells <NUM> is properly maintained by discharging the heat to the bottom plate <NUM> through the thermal transfer pad <NUM>. At this time, if a heatsink (not shown) is additionally connected to the bottom portion of the bottom plate <NUM>, the heat of the battery cells <NUM> is more actively removed.

The thermal transfer pad <NUM> is made of any material having a property capable of promoting thermal conductivity and eliminating an air layer between the bottom portion of the battery cells <NUM> and the bottom plate <NUM>. Alternatively, the thermal transfer pad <NUM> may be replaced by a thermal interface material (TIM) such as thermal grease.

Meanwhile, two objects adhered to each other has a relatively high shear strength, compared to the peel strength. Thus, when separating two objects, it is effective to apply a force in a direction perpendicular to the bonding surface.

For this reason, for the disassembling work of the battery module housing <NUM>, a detachable jig <NUM> is placed on the front surface and the rear surface of the top plate <NUM> or the bottom plate <NUM>, and then a force may be applied in a vertical direction to detach the top plate <NUM> or the bottom plate <NUM> from the other plates <NUM>, <NUM>.

However, the above method is available only after the ICB assembly is disassembled from the battery module housing <NUM>. However, as described above, the ICB assembly covers the front surface and the rear surface of the battery module housing <NUM> in a state of being welded to the electrode leads <NUM> of the battery cells <NUM>, it may not be easy to remove the ICB assembly first.

The battery module housing <NUM> according to a first embodiment and a second embodiment of the present disclosure is configured such that the detachable jig <NUM> is used at the side surface of the battery module housing <NUM>, if the detachable jig <NUM> is not useable at the front surface and the rear surface of the top plate <NUM> or the bottom plate <NUM> due to the ICB assembly (not shown).

<FIG> are diagrams corresponding to <FIG>, which show the first embodiment and the second embodiment of the present disclosure, <FIG>, <FIG> are side views and enlarged views thereof respectively showing battery module housings <NUM> according to the first embodiment and the second embodiment of the present disclosure, and <FIG> is a reference view for illustrating a method of disassembling the battery module housings <NUM> according to the first embodiment and the second embodiment of the present disclosure.

First, referring to <FIG>, common features of the battery module housings <NUM> according to the first embodiment and the second embodiment of the present disclosure will be explained. The bonding portion <NUM> according to the first embodiment and the second embodiment of the present disclosure may have a region where the adhesive <NUM> is not applied at a predetermined location. The region where the adhesive <NUM> is not applied may be used as a detachable jig insertion space <NUM> in which the detachable jig <NUM> may be partially inserted. The detachable jig insertion space <NUM> is provided in plural, and the plurality of detachable jig insertion spaces <NUM> is intermittently formed along the longitudinal direction of the first side plate <NUM> and the second side plate <NUM>.

In these embodiments, the detachable jig insertion space <NUM> is formed at both the top end and the bottom end of the battery module housing <NUM>. However, it is also possible that the detachable jig insertion space <NUM> is formed only between the top plate <NUM> and the first and second side plates <NUM>, <NUM>, namely only at a top end of the module housing <NUM>. In general, internal components of the battery module may be replaced or repaired if the top plate <NUM> is detached from the battery module housing <NUM>. Thus, it may be desirable to reduce the number of detachable jig insertion spaces <NUM> by eliminating unnecessary detachable jig insertion spaces.

The detachable jig insertion space <NUM> may be filled with a caulking member <NUM> made of a soft material. Here, the caulking member <NUM> may be, for example, any one of a sealant, a urethane foam and a rubber material in the form of a flexible foam. However, the caulking member <NUM> of the present disclosure should not be limited to the exemplified substance. In other words, any material may be used as long as it has a soft property and airtightness.

Specifically, as shown in <FIG>, the detachable jig insertion spaces <NUM> of the battery module housing <NUM> may be closed with the caulking member <NUM>. Thus, at ordinary time, the battery module housing <NUM> may be kept airtight so that moisture or other foreign matter may not flow in through the side portion. If necessary, the caulking member <NUM> may be removed and the detachable jig <NUM> can may mounted thereto.

According to the configurations of the first embodiment and the second embodiment, as shown in <FIG>, the detachable jig <NUM> may be mounted to both side surfaces of the battery module housing <NUM>, namely to the detachable jig insertion spaces <NUM>, to apply a load to the bonding portion <NUM> in the vertical direction. At this time, if it is intended to detach the top plate <NUM> at once by applying a force at a specific position, the top plate <NUM> may be plastic-deformed or broken due to the adhesive force of the other regions.

Thus, it is desired to apply a load in the vertical direction while moving the detachable jig <NUM> sequentially along the longitudinal direction of the side plate, so that the top plate <NUM> is detached from the top surfaces of the first side plate <NUM> and the second side plate <NUM> in a state where the bonding performance of the adhesive <NUM> is uniformly weakened.

Meanwhile, in the second embodiment, the detachable jig insertion space <NUM> may be extended more widely, compared to the first embodiment. That is, at least one of the first side plate <NUM> and the second side plate <NUM> according to the second embodiment of the present disclosure may further have a space expansion portion <NUM>, which is prepared by concavely forming a region to the detachable jig insertion space <NUM> to have an uneven structure.

Specifically, referring to <FIG> and <FIG>, the first side plate <NUM> and the second side plate <NUM> may be designed such that the uneven structure is repeated along the longitudinal direction of the top surface and the bottom plate. Here, the concave region may be defined as the space expansion portion <NUM>, and the space expansion portion <NUM> may be utilized as the detachable jig insertion space <NUM> since the adhesive <NUM> is not applied thereto. Thus, the detachable jig insertion space <NUM> according to the second embodiment has a larger width than the detachable jig insertion space <NUM> according to the first embodiment. With this configuration, the detachable jig <NUM> may be inserted into the detachable jig insertion space <NUM> more easily, compared with the first embodiment. Also, the detachable jig <NUM> may have a greater thickness than the first embodiment described above, which allows a greater load to be applied to the bonding portion <NUM>.

Subsequently, a third embodiment of the present disclosure will be described with reference to <FIG>. The features identical to the former embodiments will not described in detail, and features different from the former embodiments will be described in detail.

In this embodiment, the bonding portion <NUM>' of at least one of the four sites among the bonding portions <NUM> may be inclined at a predetermined angle toward the inner space S of the battery module housing <NUM>, as compared to the former embodiments.

For example, as shown in <FIG>, the battery module housing <NUM> according to the third embodiment may be fabricated in such a way that both side edges of the top plate <NUM> opposite to each other and the top surfaces of the first side plate <NUM> and the second side plate <NUM> are cut at predetermined angles, and the bonding portion <NUM>' may be formed thereon by applying the adhesive <NUM> to have a predetermined angle θ) with respect to the horizontal plane.

As shown in <FIG>, even in the third embodiment, the detachable jig insertion spaces <NUM> are intermittently provided along the longitudinal direction of the first side plate <NUM> and the second side plate <NUM>. Here, it is possible to add the space expansion portion <NUM> by applying an uneven structure to the first side plate <NUM> and the second side plate <NUM> as in the second embodiment. Also, the detachable jig insertion space <NUM> may be closed with the caulking member <NUM>, as in the former embodiments.

The disassembling operation of the battery module housing <NUM> according to the third embodiment will be briefly described. First, the bonding portion <NUM>' at an upper portion of the battery module housing <NUM> is locally heated to lower the bonding performance of the corresponding region to about <NUM> to <NUM>%. Then, the caulking member <NUM> is pushed into the inner space S of the battery module housing <NUM> or cut it out.

Then, as shown in <FIG>, the detachable jig <NUM> is inserted into the detachable jig insertion space <NUM>. At this time, the detachable jig <NUM> may use any element as long as it may be inserted into the detachable jig insertion space <NUM>. Thus, more various elements may be selected as the detachable jig <NUM>, compared to the former embodiments.

In particular, according to this embodiment, since the detachable jig <NUM> may be inserted diagonally into the bonding portion <NUM>' at the upper portion of the battery module housing <NUM>, the top plate <NUM> may be detached from the first side plate <NUM> and the second side plate <NUM> more easily with a small force, compared to the former embodiments.

Subsequently, a battery module housing <NUM> according to a fourth embodiment of the present disclosure will be briefly described with reference to <FIG>.

The battery module housing <NUM> according to the fourth embodimentincludes a bent portion <NUM>, which is formed to be bent from both edges of at least one of the top plate <NUM> and the bottom plate <NUM> and disposed in contact with the outer side surfaces of the first side plate <NUM> and the second side plate <NUM>, compared to the former embodiments.

For example, as shown in <FIG>, the top plate <NUM> according to this embodiment may be provided to surround the top surfaces and the outer side surfaces of the first side plate <NUM> and the second side plate <NUM>. The bent portion <NUM> of the top plate <NUM> may protect the bonding portion <NUM> not to be exposed to the outside and may also be used as a place where the detachable jig <NUM> may be mounted during the disassembling operation.

In particular, the detachable jig insertion space <NUM> is not present at the bonding portion <NUM> of the battery module housing <NUM> according to the fourth embodiment. That is, the battery module housing <NUM> according to the fourth embodiment has the bonding portion <NUM> where the adhesive <NUM> is successively applied, between the four plates <NUM>, <NUM>, <NUM>, <NUM>, as in the first embodiment.

In this configuration, the airtightness is superior at ordinary time, compared to the former embodiments, and if necessary, the top plate <NUM> may be detached by using the detachable jig <NUM> at the side surface of the battery module housing <NUM>.

Meanwhile, a battery module according to the present disclosure may include the battery module housing <NUM> of the present disclosure. Also, in addition to the battery module housing <NUM>, the battery module according to the present disclosure further includes battery cells <NUM> accommodated in the battery module housing <NUM>, an ICB assembly for electrically connecting the battery cells <NUM> and sensing voltage characteristics of the battery cells <NUM>, and various devices for controlling charge and discharge of the battery cells such as a BMS, a current sensor and a fuse.

The battery module may be applied to a vehicle such as an electric vehicle and a hybrid electric vehicle or a power storage system (ESS).

Claim 1:
A battery module housing (<NUM>), which includes a top plate (<NUM>) and a bottom plate (<NUM>) forming an upper wall and a lower wall, and a first side plate (<NUM>) and a second side plate (<NUM>) forming both side walls, the battery module housing having a rectangular tube shape provided to accommodate battery cells (<NUM>) in an inner space (S) thereof,
wherein the battery module housing (<NUM>) has bonding portions (<NUM>) formed by applying an adhesive (<NUM>) along a longitudinal direction to four sites corresponding to sites between both side edges of the top plate (<NUM>) opposite to each other and top surfaces of the first side plate (<NUM>) and second side plate (<NUM>) and sites between both side edges of the bottom plate (<NUM>) opposite to each other and bottom surfaces of the first side plate (<NUM>) and second side plate (<NUM>),
wherein the bonding portion (<NUM>) has a detachable jig insertion space (<NUM>) formed at a predetermined location, and the adhesive (<NUM>) is not applied to the detachable jig insertion space (<NUM>).