Patent ID: 12261278

DETAILED DESCRIPTION OF THE EMBODIMENTS

Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement them. The embodiments of the present disclosure may be modified in various different ways, and is not limited to the embodiments set forth herein.

A description of parts not related to the description will be omitted herein for clarity, and like reference numerals designate like elements throughout the description.

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

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

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

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

Below, a battery module according to the embodiments of the present disclosure will be described with reference toFIGS.3to5.

FIG.3is a perspective view showing a battery module according to embodiments of the present disclosure.FIG.4is an exploded perspective view of the battery module ofFIG.3.FIG.5is a perspective view of the battery module ofFIG.3as viewed from bottom to top of the battery module along the z-axis direction.

Referring toFIGS.3and4, a battery module100according to embodiments of the present disclosure includes a battery cell stack120in which a plurality of battery cells110are stacked, a module frame200for housing battery cell stack120, and a heat sink300located below the bottom portion210aof the module frame200. The bottom portion210aof the module frame200constitutes an upper plate of the heat sink300, and the recessed portion340of the heat sink300and the bottom portion210aof the module frame200form a coolant flow path.

First, the battery cell110may be a pouch-type battery cell. The pouch-type battery cell may be formed by housing an electrode assembly in a pouch case of a laminate sheet including a resin layer and a metal layer, and then heat-sealing a sealing part of the pouch case. At this time, the battery cell110may be formed in a rectangular sheet-like structure.

The battery cells110may be composed of a plurality of cells, and the plurality of battery cells110are stacked so as to be electrically connected to each other, thereby forming a battery cell stack120. In particular, as shown inFIG.4, a plurality of battery cells110may be stacked along a direction parallel to the x-axis.

The module frame200for housing the battery cell stack120may include an upper cover220and a U-shaped frame210.

The U-shaped frame210may include a bottom portion210aand two side portions210bextending upward from both ends of the bottom portion210a. The bottom portion210amay cover the lower surface of the battery cell stack120, and the side portions210bmay cover both side surfaces of the battery cell stack120.

The upper cover220may be formed in a single plate-shaped structure that wraps the lower surface wrapped by the U-shaped frame210and the remaining upper surface (z-axis direction) excluding the both side surfaces. The upper cover220and the U-shaped frame210can be joined by welding or the like in a state in which the corresponding corner portions are in contact with each other, thereby forming a structure that covers the battery cell stack120vertically and horizontally. The battery cell stack120can be physically protected through the upper cover220and the U-shaped frame210. For this purpose, the upper cover220and the U-shaped frame210may include a metal material having a predetermined strength.

Meanwhile, although not specifically shown, the module frame200according to modified embodiments of the present disclosure may be a mono frame in the form of a metal plate in which the upper surface, the lower surface, and both side surfaces are integrated. That is, this is not a structure in which the U-shaped frame210and the upper cover220are joined with each other, but a structure in which the upper surface, the lower surface, and both side surfaces are integrated by being manufactured by extrusion molding.

The end plate400may be located on both open sides (y-axis direction) corresponding to each other of the module frame200, so that it can be formed so as to cover the battery cell stack120. The end plate400can physically protect the battery cell stack120and other electronic instruments from external impact.

Meanwhile, although not specifically shown, a busbar frame on which a busbar is mounted and an insulating cover for electrical insulation may be located between the battery cell stack120and the end plate400.

The module frame200according to embodiments of the present disclosure includes a module frame protrusion part211formed so that the bottom portion210aof the module frame200is extended and passes through the end plate400. At this time, the coolant inflowing and discharging by the cooling port500connected to the upper surface of the module frame protrusion part211can be supplied to the heat sink300via the module frame protrusion part211and discharged from the heat sink300. The cooling port500according to embodiments of the present disclosure includes a coolant injection port500aand a coolant discharge port500b, and the coolant injection port500aand the coolant discharge port500bcan be respectively connected to a pack coolant supply tube and a pack coolant discharge tube which are described later. The module frame protrusion part211includes a first module frame protrusion part and a second module frame protrusion part from one side of the module frame200, the coolant injection port500amay be disposed on the first module frame protrusion part, and the coolant discharge port500bmay be disposed on the second module frame protrusion part.

A protrusion pattern340D may be formed on the lower plate310of the heat sink300according to the embodiments of the present disclosure. In the case of a large-area battery module in which as in the battery cell stack120according to embodiments of the present disclosure, the number of stacked battery cells is increased significantly compared to a conventional case, the width of the coolant flow path be formed wider and thus, a temperature deviation can be more severe. In the large-area battery module, it may include a case in which approximately 32 to 48 battery cells are stacked in one battery module, compared to a conventional case in which approximately 12 to 24 battery cells are stacked in one battery module. In this case, the protrusion pattern340D according to embodiments of the present disclosure can generate the effect of substantially reducing the width of the coolant flow path, thereby minimizing the pressure drop and at the same time, reducing the temperature deviation between the coolant flow path widths. Therefore, a uniform cooling effect can be realized.

Below, the heat sink according to embodiments of the present disclosure will be described in detail with reference toFIGS.4and5.

Referring toFIGS.4and5, as described above, the bottom portion210aof the module frame200constitutes an upper plate of the heat sink300, and a recessed portion340of the heat sink300and the bottom portion210aof the module frame200form a flow path for coolant.

Specifically, a heat sink300may be formed at a lower part of the module frame200, and the heat sink300may include a lower plate310that forms a skeleton of the heat sink300and is directly coupled to the bottom portion210aof the module frame200by welding, etc., an inlet320that is formed on one side of the heat sink300to supply a coolant to the inside of the heat sink300from the outside, an outlet330that is formed on one side of the heat sink300and enables the coolant flowing inside the heat sink300to flow to the outside of the heat sink300, and a recessed portion340that connects the inlet320and the outlet330and enables the coolant to flow. The inlet320and the outlet330may be formed at positions corresponding to the module frame protrusion part211so as to be connected to the lower surface of the module frame protrusion part211. For this purpose, the inlet320and the outlet330may be formed on the heat sink protrusion part300P that is protruded from one side of the heat sink300to the portion where the module frame protrusion211is located. The heat sink protrusion300P and the module frame protrusion211may be directly coupled to each other by welding or the like.

The recessed portion340of the heat sink300corresponds to a portion in which the lower plate310is formed to be recessed on the lower side. The recessed portion340may be a tube in which a cross section cut perpendicularly to the xy plane with reference to the direction in which the coolant flow path extends has U-shape, and the bottom portion210amay be located on the opened upper side of the U-shaped tube. While the heat sink30) comes into contact with the bottom portion210a, the space between the recessed portion340and the bottom portion210aforms a region through which the coolant flows, that is, a coolant flow path. Thereby, the bottom portion210aof the module frame200can come into direct contact with the coolant.

The method of manufacturing the recessed portion340of the heat sink300is not particularly limited, but by providing a structure formed so as to be recessed with respect to a plate-shaped heat sink300, a U-shaped recessed portion340with an opened upper side can be formed.

Meanwhile, although not shown, a thermal conductive resin layer containing a thermal conductive resin may be located between the bottom portion210aof the module frame200ofFIG.4and the battery cell stack120. The thermal conductive resin layer may be formed by applying a thermal conductive resin to the bottom portion210a, and curing the applied thermal conductive resin.

The thermal conductive resin may include a thermal conductive adhesive material, and specifically, may include at least one of silicone material, urethane material, and acrylic material. The thermal conductive resin is a liquid during application but is cured after application, so that it can perform the role of fixing one or more battery cells110constituting the battery cell stack120. Further, since the thermal conductive resin has excellent heat transfer properties, heat generated from the battery cell110can be quickly transferred to the lower side of the battery module.

The conventional battery module10shown inFIG.2is configured such that the heat generated from battery cells11passes through a thermal conductive resin layer40, a bottom portion31of the module frame30, a heat transfer member50, and a coolant of a heat sink60in this order, and then is transferred to the outside of the battery module10. In addition, the flow path for a coolant of the heat sink60is located inside the heat sink60.

On the other hand, the battery module100according to embodiments of the present disclosure can realize an integrated type cooling structure of the module frame200and the heat sink300, thereby further improving cooling performance. The bottom portion210aof the module frame200can perform the role of corresponding to the upper plate of the heat sink300, thereby implementing an integrated type cooling structure. The cooling efficiency due to direct cooling can be increased, and through a structure in which the heat sink300is integrated with the bottom portion210aof the module frame200, the space utilization rate on the battery module and the battery pack equipped with the battery module can be further improved.

Specifically, the heat generated from the battery cell110can pass through a thermal conductive resin layer (not shown) located between the battery cell stack120and the bottom portion210a, the bottom portion210aof the module frame200, and the coolant, and then can be transferred to the outside of the battery module100. By removing the unnecessary cooling structure according to the conventional one, the heat transfer path can be simplified and an air gap between respective layers can be reduced, and therefore, the cooling efficiency or performance can be enhanced. In particular, since the bottom portion210ais configured by an upper plate of the heat sink300and the bottom portion210acomes into direct contact with the coolant, there is an advantage that more direct cooling can be performed through the coolant. This can be distinguished from a conventional structure in which as shown inFIG.2, the upper configuration of the heat transfer member50and the heat sink60are located between the bottom portion31and the coolant, which causes a reduction in the cooling efficiency.

Further, through the removal of the unnecessary cooling structure, the height of the battery module100is reduced and thus, the cost can be reduced and space utilization rate can be increased. Furthermore, since the battery module100can be disposed in a compact manner, the capacity or output of the battery pack1000including a plurality of battery modules100can be increased.

Meanwhile, the bottom portion210aof the module frame200can be joined by welding to a portion of the lower plate310in which the recessed portion340is not formed among the heat sink300. In embodiments of the present disclosure, through the integrated type cooling structure of the bottom portion210aof the module frame200and the heat sink300, it can exhibit the effects of not only improving the cooling performance described above, but also supporting the load of the battery cell stack120housed in the module frame200and reinforcing the rigidity of the battery module100. In addition, the lower plate310and the bottom portion210aof the module frame200are sealed by welding or the like, so that the coolant can flow without leakage in the recessed portion340formed inside the lower plate310.

For effective cooling, as shown inFIG.5, the recessed portion340is preferably formed over the entire region corresponding to the bottom portion210aof the module frame200. For this purpose, the recessed portion340can be curved at least one time to connect from one side to another side. In particular, for the recessed portion340to be formed over the entire region corresponding to the bottom portion210aof the module frame200, the recessed portion340is preferably curved several times

Coolant is flown in between the bottom portion210aand the recessed portion340through the inlet320from the pack coolant supply tube described later, and the flown-in coolant moves along the coolant flow path, and then can be discharged to the pack coolant discharge tube through the outlet330. As the coolant moves from the start point to the end point of the coolant flow path formed over the entire region corresponding to the bottom portion210aof the module frame200, efficient cooling can be performed over the entire region of the battery cell stack120.

Meanwhile, the coolant is a medium for cooling and is not particularly limited, but it may be a cooling water.

Below, the structure of the battery pack according to embodiments of the present disclosure will be described in detail with reference toFIGS.6to10.

FIG.6is a perspective view showing a battery pack according to one embodiment of the present disclosure.FIG.7is an enlarged plan view of the area indicated by P in the battery pack ofFIG.6.FIG.8shows a state in which in which the pack coolant tube lower cover and the pack coolant tube upper cover are removed inFIG.7.FIG.9is a cross-sectional view taken along the cutting line9-9ofFIG.7.FIG.10is a cross-sectional view taken along the cutting line10-10ofFIG.7.

Referring toFIGS.6to10, the battery pack according to one embodiment of the present disclosure includes a plurality of battery modules100, a pack coolant tube assembly600disposed between the battery modules facing each other among the plurality of battery modules100, a pack coolant tube lower cover700for covering the lower part of the pack coolant tube assembly600, a module tray800located at the lower side of the pack coolant tube lower cover700, and a lower housing900located at the lower side of the module tray800.

Referring toFIG.6, the plurality of battery modules100included in the battery pack according to the embodiments of the present disclosure includes a first battery module and a second battery module that are arranged in two rows in a direction in which the battery cells are stacked, and face each other in a direction perpendicular to the direction in which the battery cells are stacked. The first battery module and the second battery module may refer to the battery modules100that are separated from each other on the left and right sides inFIG.6. A pack coolant tube assembly600, a pack coolant tube lower cover700and a pack coolant tube upper cover740may be disposed between the first battery module and the second battery module.

In embodiments of the present disclosure, the pack coolant tube assembly600is disposed between the battery modules100adjacent to each other. In a space between the battery modules100adjacent to each other in which the pack coolant tube assembly600is disposed, all of the cooling ports500formed in each of the battery modules100adjacent to each other may be disposed. At this time, a coolant injection port510formed in one battery module and a coolant discharge port520formed in another battery module100among the battery modules100adjacent to each other may be disposed while facing each other.

Referring toFIG.8, the pack coolant supply tube621and the pack coolant discharge tube622may be extended while intersecting with each other. By having such an arrangement structure of the pack coolant tube620, an integrated type structure of the plurality of battery modules100and the cooling structure can be implemented inside the battery pack, thereby enhancing the space utilization rate and at the same time, improving the cooling efficiency. The height of the pack coolant supply tube621and the height of the pack coolant discharge tube622may be different from each other, so that the pack coolant tube620can have the arrangement structure as described above. The portion where the height of the pack coolant supply tube621and the height of the pack coolant discharge tube622are different from each other can be partially formed.

Referring toFIGS.8to10, the connection port610connects the cooling port500and the pack coolant tube620. More specifically, the cooling port500includes a coolant injection port510and a coolant discharge port520, the pack coolant tube620includes a pack coolant supply tube621connected to the coolant injection port510and a pack coolant discharge tube622connected to the coolant discharge port520, and the connection port610may connect between the coolant injection port510and the pack coolant supply tube621and between the coolant discharge port520and the pack coolant discharge tube622, respectively. The connection ports610are connected to coolant injection ports510that supply the coolant to the plurality of battery modules100and coolant discharge ports520that discharge the coolant from the plurality of battery modules100, respectively.

The pack coolant tube lower cover700houses the pack coolant tube assembly600and covers the coolant leaked from the pack coolant tube assembly600so as not to leak to the peripheral battery module. At the same time, the coolant leaked through the lower cover opening described later can be guided to the lower space of the battery pack.

The module tray800can be formed in a structure in which it is located at the lower side of the plurality of battery modules100and thus, the plurality of battery modules100can be disposed and seated at a designated position. In addition, a plurality of battery modules100are disposed so as to be separated from each other through the module tray800, and a space for component arrangement may be provided so that the pack coolant tube assembly600can be located in the separated space.

As shown inFIG.10, the lower housing900is located at the lower side of the module tray800. A space S is formed between the lower housing900and the module tray800. According to embodiments of the present disclosure, the lower cover opening710is formed in the pack coolant tube lower cover700, and the lower cover opening710is connected to a space S formed between the module tray800and the lower housing900. Therefore, the coolant leaked from the pack coolant tube assembly600can be guided to a space S formed between the module tray800and the lower housing900through the lower cover opening710.

In a cooling structure using a fluid, it is possible to generate a situation where the coolant leaks due to defective products or accidents during transportation of products, and the leaked coolant penetrates into the inside of electrical components to cause a short-circuit, whereby there is a danger of causing a fire in the battery pack. Therefore, when the coolant leaks, it is necessary to prevent the leaked coolant from penetrating into the electrical components in advance.

Thus, according to embodiments of the present disclosure, when the coolant leaks from the various members forming the cooling structure and the connection parts of those members, the is guided to a predetermined path and stored in the space S between the module tray800and the lower housing900under the battery pack, thereby capable of penetrating the leaked coolant into the inside of the electrical components and preventing in advance the possibility of the occurrence of a fire through a short circuit.

Below, a coolant induction structure according to one embodiment of the present disclosure will be described in more detail with reference toFIGS.9to13.

FIG.11is a schematic diagram showing the configuration of a portion which is cut along the cutting line9-9ofFIG.7.FIG.12is a schematic view showing the configuration of a portion which is cut along the cutting line10-10ofFIG.7.FIG.13is an exploded perspective view of a coolant leakage preventive structure of a battery pack according to one embodiment of the present disclosure.

Referring toFIG.12, the cooling port500according to the embodiments of the present disclosure may be located on the lower cover opening710. More specifically, the cooling port500may be formed on the module frame protrusion part211so as to pass through the inside of the lower cover opening710from the lower side to the upper side. Through this, the coolant leaked from the cooling port500, the connection port610connected thereto, and the pack coolant tubes620can be guided to the lower space S through the lower cover opening710.

Referring toFIGS.9and11, among the battery modules100facing each other, the cooling port500formed in one battery module and the cooling port500′ formed in another battery module are disposed so as to face each other, the lower cover opening710is formed in plural numbers, and the two cooling ports500and500′ disposed so as to face each other may be located together on one lower cover opening among the plurality of the lower cover openings710. Thereby, the coolant leaked from the two cooling ports500and500′ facing each other and located adjacent to each other can be guided to the lower space S at once.

The module tray800includes a module tray opening810, and the cooling port500may be located on the module tray opening810. At this time, the lower cover opening710may be connected to a space S formed between the module tray800and the lower housing900through the module tray opening810.

According to embodiments of the present disclosure, the battery pack may further include a module tray gasket820formed between the module tray800and the lower housing900. The module tray800is integrally formed along the outer edge portion of each of the plurality of battery modules100, and the module tray gasket820may be formed along an outer edge portion of the module tray800. The module tray gasket820can seal between the module tray800and the lower housing900. Thereby, the coolant flowing into the space S between the module tray800and the lower housing900can be prevented from leaking to the outside.

The battery pack may further include a lower cover gasket720formed between the pack coolant tube lower cover700and the module tray800. The lower cover gasket720may be formed outside the lower cover opening710and the module tray opening810. The lower cover gasket720can seal between the pack coolant tube lower cover700and the module tray800. In order to prevent the coolant flowing in through the lower cover opening710from leaking between the module tray800and the pack coolant tube lower cover700, the lower cover gasket720seals between the module tray800and the pack coolant tube lower cover700, and the coolant passing through the lower cover opening710can pass through the module tray opening810and flow in a space S between the module tray800and the lower housing900without leakage.

According to the embodiments of the present disclosure, as shown inFIG.13, the battery pack may further include a pack coolant tube upper cover740for covering the upper part of the pack coolant tube assembly600. The pack coolant tube upper cover740may physically protect the pack coolant tube assembly600from external impact together with the pack coolant tube lower cover700.

The battery pack according to embodiments of the present disclosure described above can have a structure in which one or more of the battery modules according to the present embodiment are gathered, and packed together with a battery management system (BMS) and a cooling device that control and manage battery's temperature, voltage, etc.

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

Although the invention has been shown and described with reference to the preferred to embodiments, the scope of the present disclosure is not limited thereto, and numerous other modifications and embodiments made by those skilled in the art will also fall within the spirit and scope of the principles of the invention described in the appended claims.

DESCRIPTION OF REFERENCE NUMERALS

200: module frame211: module frame protrusion part300: heat sink500: cooling port600: pack coolant tube assembly610: connection port620: pack coolant tube621: pack coolant supply tube622: pack coolant discharge tube700: pack coolant tube lower cover710: lower cover opening720: lower cover gasket740: pack coolant tube upper cover800: module tray810: module tray opening820: module tray gasket900: lower housing