Patent Description:
As technical developments and demands on mobile devices increase, demands on rechargeable batteries as energy sources are steeply increasing. Accordingly, studies on the rechargeable batteries for satisfying various demands are in active progress.

The rechargeable batteries are gaining much attention as energy sources for power-based devices such as electric bicycles, electric vehicles, and hybrid electric vehicles in addition to mobile devices such as mobile phones, digital cameras, and laptops.

Small battery packs to which a single battery cell is packed are used in small devices such as cellular phones and cameras, and mid-sized or large battery packs to which a battery module or a battery pack having two or more battery cells connected in parallel and/or in series are packed are used in mid-sized/large devices such as laptops and electric vehicles. Therefore, the number of battery cells included in the battery pack may be set in various ways according to a required output voltage or charging and discharging capacity.

In addition, when a battery pack is configured by connecting a plurality of battery cells in series/parallel, a battery module formed with at least one battery cell is configured in advance, and other constituent elements are added thereto by using at least one battery module to configure a battery pack, which is a general method.

Regarding the battery module, importance of the method for efficiently cooling heat generated by the battery cell according to the increase of required battery capacity is gradually increasing. For this purpose, a configuration for improving thermal conductivity by applying a heat radiating resin into a case of the battery module has been introduced.

However, when the heat radiating resin is injected into the case through an injection hole in the battery module, the heat radiating resin may not be stably applied in a designated area but may be applied at a lesser amount or may be excessively applied therein, thereby exercising a negative influence to cooling performance or increasing an expense.

The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention, and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

The present invention has been made in an effort to provide a battery module for providing excellent liquid-injection quality and cooling performance by stably applying a heat radiating resin, reducing a cost of a manufacturing process, and improving efficiency, and a manufacturing method thereof.

However, tasks to be solved by exemplary embodiments of the present invention may not be limited to the above-described tasks, and may be extended in various ways within a range of technical scopes included in the present invention.

The present invention, as defined in the pending set of claims, is a battery module including: a battery cell stacked body in which a plurality of battery cells are adjacent each other in parallel and are stacked; a mono frame receiving the battery cell stacked body and including at least one opening opened in a length direction of the battery cell stacked body, and including an upper plate and a lower plate that are perpendicular to a stacked side of the battery cell stacked body and a pair of lateral plates in parallel to the stacked side of the battery cell stacked body; an external expansion controlling pad provided between the battery cell stacked body and the mono frame; and a heat radiating resin provided between the battery cell stacked body and the lower plate, wherein the external expansion controlling pad includes two main bodies covering one side of the battery cell stacked body and provided between the battery cell stacked body and the pair of lateral plates, and two bridges connecting the two main bodies and formed along a side of the battery cell stacked body between the battery cell stacked body and the lower plate.

The heat radiating resin is provided in a space formed by the two main bodies and the two bridges.

The lower plate may include a plurality of injection holes for injecting the heat radiating resin.

The heat radiating resin may be a thermal resin.

The battery module may further include a plurality of internal expansion controlling pads provided between the plurality of battery cells.

The external expansion controlling pad and the plurality of internal expansion controlling pad may include a polyurethane or an ethylene propylene diene monomer (EDPM).

Another embodiment of the present invention provides a method for manufacturing a battery module, including: manufacturing a battery cell stacked body in which a plurality of battery cells are provided adjacent to each other in parallel and are stacked; forming an external expansion controlling pad including two main bodies for covering a battery cell provided on an outermost side of the battery cell stacked body and two bridges connecting the two main bodies and formed along a side of the battery cell stacked body; allowing the battery cell stacked body in which the external expansion controlling pad is formed to be received in a mono frame; and injecting a heat radiating resin into a space formed by the two main bodies and the two bridges between the mono frame and the battery cell stacked body.

When the heat radiating resin is injected, the two main bodies and the two bridges may function as a dam for preventing the heat radiating resin from running down to the outside.

The mono frame may include at least one opening opened in a length direction of the battery cell stacked body, and may include an upper plate and a lower plate that are perpendicular to a stacked side of the battery cell stacked body and a pair of lateral plates in parallel to the stacked side of the battery cell stacked body, and the heat radiating resin may be injected between a lower plate of the mono frame and the battery cell stacked body.

The injection of the heat radiating resin may be performed while the battery module is disposed so that the lower plate may face upwards with respect to a gravity direction.

The lower plate may include a plurality of injection holes for injecting the resin.

According to the exemplary embodiments, regarding the battery module into which the heat radiating resin is injected, the battery module for providing excellent liquid-injection quality and cooling performance by stably applying a heat radiating resin, reducing a cost of a manufacturing process without providing an additional process, and improving efficiency, and the manufacturing method thereof, may be provided.

The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown.

The drawings and description are to be regarded as illustrative in nature and not restrictive, and like reference numerals designate like elements throughout the specification.

Further, the size and thickness of each configuration shown in the drawings are arbitrarily shown for better understanding and ease of description, and the present invention is not limited thereto. In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. For better understanding and ease of description, the thicknesses of some layers and areas are exaggerated.

It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present. The word "on" or "above" means positioned on or below the object portion, and does not necessarily mean positioned on the upper side of the object portion based on a gravitational direction.

Unless explicitly described to the contrary, the word "comprise" and variations such as "comprises" or "comprising" will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.

The phrase "on a plane" means viewing the object portion from the top, and the phrase "on a cross-section" means viewing a cross-section of which the object portion is vertically cut from the side.

<FIG> shows a perspective view of a battery module according to an exemplary embodiment of the present invention, and <FIG> shows a perspective view of a battery module shown in <FIG> that is rotated by <NUM> degrees.

Referring to <FIG> and <FIG>, the battery module <NUM> according to an exemplary embodiment of the present invention includes a battery cell stacked body <NUM> in which battery cells <NUM> are attacked, and a mono frame <NUM> into which the battery cell stacked body <NUM> is received.

The battery cell stacked body <NUM> is an assembly of a rechargeable battery including a plurality of battery cells <NUM>. The battery cell stacked body <NUM> may include a plurality of battery cells <NUM>, and each battery cell includes an electrode lead <NUM>. The battery cell <NUM> may be a pouch-type battery cell having a planar shape, but is not limited thereto. The electrode lead <NUM> is a positive lead or a negative lead, the electrode lead <NUM> of the battery cell <NUM> includes an end that may be bent in one direction, and it may accordingly contact an end of an electrode lead of another adjacent battery cell <NUM>. The two electrode leads <NUM> contacting each other may be fixed by welding the same with each other, and by this, the battery cells <NUM> inside the battery cell stacked body <NUM> may be electrically connected to each other.

A plurality of battery cells <NUM> are perpendicularly stacked so that the electrode leads <NUM> may be arranged in one direction, thereby forming the battery cell stacked body <NUM>
The battery cell stacked body <NUM> includes at least one opening <NUM> opened in a length direction of the battery cell stacked body <NUM>, and is received into the mono frame <NUM> including an upper plate <NUM> and a lower plate <NUM> that are perpendicular to a stacked side of the battery cell stacked body <NUM>, and a pair of lateral plates <NUM> in parallel to the stacked side of the battery cell stacked body <NUM>. In this instance, the electrode leads <NUM> may be exposed through the opening <NUM>, and the opening <NUM> may be covered by an end plate (not shown) including a configuration for electrically connecting the electrode lead <NUM> to the outside.

A plurality of injection holes <NUM> for injecting a heat radiating resin <NUM> to be described are formed in the lower plate <NUM> of the mono frame <NUM>. That is, while the battery cell stacked body <NUM> is received in the mono frame <NUM>, as shown in <FIG>, the battery module <NUM> is disposed so that the lower plate <NUM> may be provided to a top thereof, and the heat radiating resin <NUM> is injected through the injection hole <NUM> in the lower plate <NUM>. A detailed description thereof will be described in a later portion of the present specification.

The heat radiating resin <NUM> and expansion controlling pads <NUM> and <NUM> provided in the mono frame <NUM> will now be described with reference to <FIG> together with <FIG> and <FIG>.

<FIG> shows a perspective view on a state that a mono frame is removed from <FIG>, <FIG> shows a cross-sectional view with respect to a line III-III' of <FIG>, and <FIG> shows a developed diagram of an external expansion controlling pad according to an exemplary embodiment of the present invention.

The heat radiating resin <NUM> is provided between the battery cell stacked body <NUM> and the lower plate <NUM>. The heat radiating resin <NUM> is made of a heat conducting material so that the heat generated by the battery cell stacked body <NUM> may be discharged to the outside, and for example, it may be made of a thermal resin. Examples of the thermal resin include silicon, urethane, and epoxy.

The heat radiating resin <NUM> is injected through the injection hole <NUM> formed in the lower plate <NUM>. In this case of injection, when the injection amount of the resin is appropriately adjusted, the same may be sufficiently injected to a desired portion, that is, between the battery cell stacked body <NUM> and the lower plate <NUM>. When the injection amount is too small, the heat radiating resin <NUM> is not uniformly formed over the whole lower plate <NUM>, so the heat is insufficiently discharged. When the injection amount is too large, the heat radiating resin <NUM> flows to an unneeded portion, so drawbacks that the manufacturing cost caused by the loss of resources may increase and the quality at the portion where the heat radiating resin <NUM> overflows may be deteriorated are generated. Therefore, there is a need to form the heat radiating resin <NUM> at the desired space by appropriately controlling the injection amount of the heat radiating resin <NUM>.

For this purpose, in the present exemplary embodiment, as shown in <FIG> and <FIG>, the injection space of the heat radiating resin <NUM> is obtained by using the external expansion controlling pad <NUM>. The external expansion controlling pad <NUM> is provided between the battery cell stacked body <NUM> and the mono frame <NUM>, and in detail, it includes two main bodies <NUM> covering one side of the battery cell stacked body <NUM>, and provided between the battery cell stacked body <NUM> and a pair of lateral plates <NUM>, and two bridges <NUM> connecting the two main bodies <NUM>, and formed along a side of the battery cell stacked body <NUM> between the battery cell stacked body <NUM> and the lower plate <NUM>.

The heat radiating resin <NUM> is provided in a space formed on the two main bodies <NUM> and the two bridges <NUM>. As shown in <FIG>, when the two main bodies <NUM> are provided to contact respective sides of the battery cell stacked body <NUM>, a portion protruding to be higher than the battery cell stacked body <NUM> configures a long side of the space in which the heat radiating resin <NUM> is provided, and the two bridges <NUM> provided between the battery cell stacked body <NUM> and the lower plate <NUM> configure a short side of the space in which the heat radiating resin <NUM> is provided. By this, a space partitioned by the two main bodies <NUM> and the two bridges <NUM> is formed between the lower plate <NUM> and the battery cell stacked body <NUM>, and the heat radiating resin <NUM> is injected through the injection hole <NUM> of the lower plate <NUM> to fill the corresponding space.

In this instance, the above-described two main bodies <NUM> and two bridges <NUM> function as a dam for preventing the heat radiating resin <NUM> from overflowing. That is, when the heat radiating resin <NUM> is excessively injected, the heat radiating resin <NUM> may flow down along a corner of the battery cell stacked body <NUM>, and according to the present exemplary embodiment, the effect of injecting the heat radiating resin <NUM> into a desired portion without it flowing down may be obtained by the two main bodies <NUM> and the two bridges <NUM> functioning as a dam.

Particularly, according to the present exemplary embodiment, for the above-noted dam function, the above-noted effect may be simply achieved by differently cutting the pad installed for an expansion control without providing additional parts or adding a design. That is, as shown in <FIG>, the two main bodies <NUM> corresponding to the stacked side of the battery cell stacked body <NUM> and the two bridges <NUM> connecting the two main bodies <NUM> and formed along the side of the battery cell stacked body <NUM> are connected to each other and are integrally formed, so the space (A) into which the heat radiating resin <NUM> is injected may be obtained by cutting the expansion controlling pad in this shape and applying the same to the battery cell stacked body <NUM>.

Further, as the two main bodies <NUM> and the two bridges <NUM> function as a dam, the heat radiating resin <NUM> may be injected up to a predetermined injection amount without overflowing without performing a precise control to the heat radiating resin <NUM>, so there is no need to install a large number of injection holes for the purpose of controlling the injection amount, and the injection facilities may be simplified.

The height that is a protrusion of the two main bodies <NUM> from the battery cell stacked body <NUM> and the thickness of the two bridges <NUM> may be appropriately selected by considering a type and viscosity of the heat radiating resin <NUM>, and they are not specifically limited thereto.

The expansion controlling pad may further include, in the battery cell stacked body <NUM>, a plurality of internal expansion controlling pads <NUM> provided between the battery cells <NUM>. The internal expansion controlling pads <NUM> may have substantially the same area as the stacked side of the battery cell stacked body <NUM>, and may be inserted each time three to four battery cells <NUM> are stacked, but are not limited thereto, and the number and the thickness may be appropriately adjusted as needed.

The internal expansion controlling pad <NUM> and the external expansion controlling pad <NUM> may control cell swelling as they are compressed and perform a buffering function when the battery cells <NUM> expand, thereby preventing the battery cells <NUM> and the mono frame <NUM> from being damaged by the expansion of the battery cells <NUM>. For this purpose, the internal expansion controlling pad <NUM> and the external expansion controlling pad <NUM> may include a material including a soft elastic substance such as polyurethane (PU) or ethylene propylene diene monomer (EDPM). The above-noted material has excellent absorption of vibration and a repulsive force on compression, so when a cell swelling phenomenon is generated to a plurality of battery cells <NUM>, a guide function may be performed so that the battery module <NUM> with excellent dimensional stability may be provided.

As described above, as the external expansion controlling pad <NUM> including two main bodies <NUM> and two bridges <NUM> functions as a dam so that the heat radiating resin <NUM> injected between the battery cell stacked body <NUM> and the lower plate <NUM> of the mono frame <NUM> may not flow, so the battery module <NUM> for providing excellent liquid-injection quality and cooling performance by stably applying the heat radiating resin <NUM> without a special additional process, reducing the expense of the manufacturing process, and improving efficiency may be provided.

A method for manufacturing a battery module according to an exemplary embodiment of the present invention will now be described with reference to <FIG>.

<FIG> shows a flowchart of a method for manufacturing a battery module according to an exemplary embodiment of the present invention.

A plurality of battery cells <NUM> are stacked, and they are connected with an electrode lead <NUM> to form a battery cell stacked body <NUM> (S10).

In this instance, a plurality of internal expansion controlling pads <NUM> may be stacked together between a plurality of battery cells <NUM> to form the same.

An external expansion controlling pad <NUM> including two main bodies <NUM> for covering the battery cell provided on the outermost side of the battery cell stacked body <NUM> and two bridges <NUM> connecting the two main bodies <NUM> and formed along a side of the battery cell stacked body <NUM> is formed (S20).

That is, the external expansion controlling pad <NUM> is formed by cutting the expansion controlling pad as shown in <FIG> in the form in which two main bodies <NUM> corresponding to the stacked side of the battery cell stacked body <NUM> and two bridges <NUM> connecting the same are connected to each other and are integrally formed. The two main bodies <NUM> of the external expansion controlling pad <NUM> are disposed to respectively cover the battery cell provided on the outermost side of the battery cell stacked body <NUM>, and hence, the two bridges <NUM> provided between the two main bodies <NUM> are disposed along the sides of the battery cell stacked body <NUM>.

An assembly of the battery cell stacked body <NUM> and the external expansion controlling pad <NUM> is received in the mono frame <NUM> (S30).

In this instance, the two bridges <NUM> are provided on the lower plate <NUM> of the mono frame <NUM>, and the two main bodies <NUM> are disposed to respectively face the lateral plate <NUM> of the mono frame <NUM>. The electrode lead <NUM> of the battery cell stacked body <NUM> is exposed through an opening <NUM> of the mono frame <NUM>, and in this instance, the opening <NUM> may be covered with an end plate (not shown) including a configuration for electrically connecting the electrode lead <NUM> to the outside.

The mono frame <NUM> is rotated by <NUM> degrees so that the lower plate <NUM> may face upwards with respect to a gravity direction, and the heat radiating resin <NUM> is injected through a plurality of injection holes <NUM> formed in the lower plate <NUM> (S40).

In this instance, the above-described two main bodies <NUM> and two bridges <NUM> function as a dam for preventing the heat radiating resin <NUM> from overflowing. That is, when the heat radiating resin <NUM> is excessively injected, the heat radiating resin <NUM> may run down along a corner of the battery cell stacked body <NUM>, but according to the present exemplary embodiment, the effect that the heat radiating resin <NUM> is injected into the desired portion without running down by the two main bodies <NUM> and the two bridges <NUM> functioning as a dam is provided.

A viscosity of the injected heat radiating resin <NUM> may be <NUM>,<NUM> cP to <NUM>,<NUM> cP. However, when the configuration according to the present invention is applied, it includes the two main bodies <NUM> and the two bridges <NUM> functioning as a dam, so the heat radiating resin <NUM> may be applied to the desired area irrespective of resin characteristics such as dynamic flowability, viscosity, or a resin type, and running down to an undesired area may be prevented, and the viscosity of the heat radiating resin <NUM> may be applied without specific limits.

When injection of the heat radiating resin <NUM> injected as a liquid is finished, it may be completed by natural hardening.

Claim 1:
A battery module (<NUM>) comprising:
a battery cell stacked body (<NUM>) in which a plurality of battery cells are adjacent each other in parallel and are stacked;
a mono frame (<NUM>) receiving the battery cell stacked body (<NUM>) and including at least one opening opened in a length direction of the battery cell stacked body (<NUM>), and including an upper plate (<NUM>) and a lower plate (<NUM>) that are perpendicular to a stacked side of the battery cell stacked body (<NUM>) and a pair of lateral plates (<NUM>) in parallel to the stacked side of the battery cell stacked body (<NUM>);
an external expansion controlling pad (<NUM>) provided between the battery cell stacked body (<NUM>) and the mono frame (<NUM>); and
a heat radiating resin (<NUM>) provided between the battery cell stacked body (<NUM>) and the lower plate (<NUM>),
wherein the external expansion controlling pad (<NUM>) includes two main bodies (<NUM>) covering one side of the battery cell stacked body (<NUM>) and provided between the battery cell stacked body (<NUM>) and the pair of lateral plates (<NUM>), and two bridges (<NUM>) connecting the two main bodies (<NUM>) and formed along a side of the battery cell stacked body (<NUM>) between the battery cell stacked body (<NUM>) and the lower plate (<NUM>),
wherein the heat radiating resin (<NUM>) is provided in a space formed by the two main bodies (<NUM>) and the two bridges (<NUM>).