Battery module having improved cooling structure

A battery module having an improved cooling structure according to an embodiment of the present disclosure comprises: a pouch cell laminate comprising a first pouch cell and a second pouch cell located adjacent to the first pouch cell; and cooling fins configured to surround the circumference of an accommodation portion of each of the first pouch cell and the second pouch cell.

TECHNICAL FIELD

The present application claims priority to Korean Patent Application No. 10-2015-0124382 filed on Sep. 2, 2015 in the Republic of Korea, the disclosure of which is incorporated herein by reference.

The present disclosure relates to a battery module, and more particularly, to a battery module having an improved cooling structure by optimizing shapes and installation positions of cooling fins.

BACKGROUND ART

With the technical development of mobile devices and the increased demand for the mobile devices, a demand for batteries serving as energy sources has sharply increased. Thus, a vast amount of research into batteries capable of meeting various needs has progressed.

Typically, batteries comprise can-type secondary batteries and pouch-type secondary batteries, which may have small thicknesses and be applied to products, such as mobile phones.

In addition, typical secondary batteries may be classified according to structure of an electrode assembly comprising a positive electrode plate, a negative electrode plate, and a separator. Typically, electrode assemblies may comprise a jelly-roll-type (wind-type) electrode assembly in which long-sheet-type positive electrodes and negative electrodes are wound with a separator interposed therebetween, a stack-type electrode assembly in which a plurality of positive electrodes and negative electrodes that are cut into a predetermined unit size are sequentially stacked with a separator interposed therebetween, and a stack/folding-type electrode assembly in which bi-cells or full cells in which positive electrodes and negative electrodes provided in predetermined units are stacked with a separator interposed therebetween are wound.

Generally, a pouch-type secondary battery comprises a pouch external member, an electrode assembly accommodated in the pouch external member, and an electrode lead electrically connected to the electrode assembly and withdrawn outwardly from the pouch external member.

The pouch external member may be formed to such a size as to accommodate the electrode assembly and the electrode lead, which will be described below.

The electrode assembly comprises a positive electrode plate, a negative electrode plate, and a separator. In the electrode assembly, the positive electrode plate and the negative electrode plate are sequentially stacked with the separator interposed therebetween, forming a stack type or a stack/folding type.

Although the pouch-type secondary battery is usable alone, there are many cases in which a battery module comprising a plurality of electrically connected pouch-type secondary batteries or a battery pack comprising a plurality of connected battery modules is used to increase capacity or output.

Since the battery module or the battery pack is embodied by connecting a plurality of pouch-type secondary batteries, heat generated by the respective secondary batteries may collect, and the generated heat may further increase due to a close-packed structure of the secondary batteries.

Accordingly, in the unit of the battery module or the battery pack, a structure, such as a heat radiation fin configured to radiate heat, may be further provided between every two pouch-type secondary batteries.

However, due to such a combined structure, configuration of the battery module or the battery pack may be complicated. An additional thermal conduction structure is formed between the pouch-type secondary batteries so that the entire size of the battery module or the battery pack may increase. Thus, the battery module or the battery pack may be disadvantageous in terms of energy density, which is a very significant factor in the field of secondary batteries.

DISCLOSURE

Technical Problem

The present disclosure is designed to solve the problems of the related art, and therefore the present disclosure is directed to increasing cooling efficiency of a battery module without reducing energy density of the battery module due to the installation of a structure for cooling.

The technical objectives of the present disclosure are not limited to the above disclosure; other objectives may become apparent to those of ordinary skill in the art based on the following descriptions.

Technical Solution

In one aspect of the present disclosure, there is provided a battery module having an improved cooling structure. The battery module comprises a pouch cell laminate comprising a first pouch cell and a second pouch cell located adjacent to the first pouch cell, and cooling fins configured to surround circumference of an accommodation portion of each of the first pouch cell and the second pouch cell.

The battery module may further comprise a cooling plate located on one side of the pouch cell laminate and configured to contact the cooling fins.

The cooling fins may composed of aluminum.

The cooling fins may be in contact with a sealing portion of each of the first pouch cell and the second pouch cell.

In the battery module, the accommodation portion of the first pouch cell and the accommodation portion of the second pouch cell may be in contact with each other.

The cooling fins may be configured to surround, all at once, the circumferences of the accommodation portions of the first pouch cell and the second pouch cell, which are in contact with each other.

Advantageous Effects

According to the present disclosure, cooling efficiency of a battery module can be improved without reducing energy density of the battery module due to the installation of a structure for cooling.

MODE FOR DISCLOSURE

A battery module according to an embodiment of the present disclosure will be described with reference toFIGS. 1 to 3.

FIG. 1is a perspective view of a battery module according to an embodiment of the present disclosure.FIG. 2is a side view of a battery module according to an embodiment of the present disclosure.FIG. 3is a plan view of cooling fins installed at a pouch cell applied to a battery module according to an embodiment of the present disclosure.

Referring toFIGS. 1 to 3, a battery module according to an embodiment of the present disclosure comprises at least two pouch cells10and cooling fins20, and may further comprise a cooling plate30, which contacts the cooling fins20.

The pouch cell10comprises an electrode assembly (not shown), a pair of electrode leads14connected to the electrode assembly, and a pouch case11configured to accommodate the electrode assembly and be hermetically sealed with the electrode leads14withdrawn outwardly.

The electrode assembly comprises a positive electrode plate, a negative electrode plate, and a separator. The electrode assembly may be embodied by sequentially stacking a positive electrode plate and a negative electrode plate with a separator interposed, at least once. The electrode assembly may have various structures, such as a wind type, a stack type, or a stack/folding type, according to embodiment.

The positive electrode plate applied to the electrode assembly comprises a positive electrode collector composed of a highly conductive metal sheet, for example, aluminum (Al) foil, and a positive electrode active material layer formed on one surface or both surfaces of the positive electrode collector. Also, the positive electrode plate is provided to have a region in which the positive electrode active material layer is not formed, namely, a positive electrode non-coating unit.

The negative electrode plate applied to the electrode assembly comprises a negative electrode collector composed of a highly conductive metal sheet, for example, copper (Cu) foil, and a negative electrode active material layer formed on one surface or two surfaces of the negative electrode collector. Also, the negative electrode plate is provided to have a region in which the negative electrode active material layer is not formed, namely, a negative electrode non-coating unit.

The separator is located between the positive electrode plate and the negative electrode plate and electrically insulates the positive electrode plate and the negative electrode plate from each other. The separator may be formed as a porous film type so that lithium ions may move between the positive electrode plate and the negative electrode plate. The separator may be composed of, for example, a porous film using polyethylene (PE), polypropylene (PP), or a composite film thereof.

The electrode lead14is a component, which is connected to the electrode assembly and withdrawn outwardly from the pouch case11and configured to connect the electrode assembly with an external component. The electrode lead14corresponds to a concept including a positive electrode lead connected to the positive electrode plate and a negative electrode lead connected to the negative electrode plate. More specifically, the positive electrode lead is connected to a positive electrode non-coating unit provided on the positive electrode plate, while the negative electrode lead is connected to a negative electrode non-coating unit provided on the negative electrode plate.

The pouch case11composed of a multilayered-film-type external member comprising a metal layer and a resin layer configured to surround the metal layer. The pouch case11may include an upper case and a lower case.

When the pouch case11includes the upper case and the lower case as described above, each of the upper case and the lower case is provided to have an accommodation portion12configured to provide a space in which the electrode assembly is accommodated, and a sealing portion13corresponding to an outer circumferential region of the accommodation portion12.

In this case, the electrode assembly is accommodated in the accommodation portions12of the upper case and the lower case, and the sealing portions13of the upper case and the lower case are bonded to each other due to thermal fusion while being in contact with each other. Thus, the pouch case11is hermetically sealed. An electrolyte may be injected into the pouch case11before or after the pouch case11is sealed.

Although the present disclosure illustrates only a case in which a pair of electrode leads14are withdrawn in opposite directions to each other in each of the pouch cells10, the present disclosure is not limited thereto. That is, it is clearly revealed that the pouch cell10may be embodied by withdrawing a pair of electrode leads14in the same direction when necessary.

In addition, although not shown, an adhesive film (not shown) interposed between an inner side surface of the sealing portion12and the electrode lead14may be further used so that the electrode lead14withdrawn outwardly from the pouch case11may be easily adhered to the inner side surface of the sealing portion12.

The cooling fins20may be composed of a highly thermally conductive metal material, for example, aluminum (Al).

The cooling fins20are in contact with the pouch cell10and located to surround the circumference of the accommodation portion12of the pouch cell10so that heat generated by the pouch cell10may be efficiently emitted.

To improve thermal emission effects, the cooling fins20may be in contact with not only the accommodation portion12but also the sealing portion13. When the cooling fins20are in contact with both the accommodation portion12and the sealing portion13of the pouch cell10as described above, heat generated by the electrode assembly and the electrode lead14may be efficiently radiated during a process of using the battery module.

In the process of using the battery module, generated heat concentrates on the electrode lead14of the pouch cell (10). When the cooling fins20are in contact with the sealing portion13, heat that has concentrated on the electrode lead14withdrawn through the sealing portion13may be efficiently distributed so as to improve cooling efficiency.

When the cooling fins20are applied to a cell laminate comprising at least two pouch cells10, the cooling fins20may have such a size and shape as to surround, all at once, the circumferences of the accommodation portions12of a first pouch cell and a second pouch cell, which are adjacent to each other.

When one of the cooling fins20surrounds, all at once, the circumferences of the accommodation portions12of the two pouch cells10, which are adjacent to each other, the battery module is advantageous in terms of both process efficiency and cooling efficiency.

The cooling fins20may be in contact with not only the accommodation portion12of each of two pouch cells10, which are adjacent to each other, but also the sealing portion13of each of the two pouch cells10. In this case, as explained above, heat that has concentrated on the electrode pad14of each of two pouch cells10, which are in contact with each other, may be efficiently distributed so as to further increase cooling efficiency.

Although the present disclosure illustrates only an example in which a pouch cell laminate comprises three pouch cells10and two cooling fins20, the present disclosure is not limited thereto.

That is, it is clearly revealed that the pouch cell laminate may comprise two, four, or more pouch cells10and thus, one, three, or more cooling fins20may be applied to the pouch cell laminate unlike the illustration in the drawings.

The cooling plate30is located on one side and/or both sides of a widthwise direction of the pouch cell10. Here, the widthwise direction of the pouch cell10refers to a direction perpendicular to a direction in which the electrode lead (14) is withdrawn, namely, an upward/downward direction on the basis ofFIG. 3. The cooling plate30is in contact with the cooling fins20installed in the pouch cell laminate and radiates heat transmitted through the cooling fins20.

In view of the functions of the cooling plate30, the cooling plate30may be composed of a highly thermally conductive metal material, for example, an aluminum (Al) material, like the cooling fins20.

While the present disclosure has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that it is capable of various changes and modifications without departing from the scope of the present disclosure as defined by the following claims.