BATTERY PACK

The battery pack includes a first case, a second case coupled with the first case, a plurality of battery cells which are received between the first case and the second case and are positioned side-by-side, and a label comprising a first surface attached to an outer surface of the first case and a second surface attached to an outer surface of the second case, in which a side coupling portion of the first case and the second case forms an outwardly convex round shape, the label comprises an intermediate surface which encloses an outer circumferential surface of the side coupling portion, and the intermediate surface is formed continuous from the first surface and the second surface. Thus, area and thickness of a label-attached portion of a case on which a label is attached may be minimized, allowing a slim structure of a battery pack.

DETAILED DESCRIPTION

The present invention will become apparent from embodiments described below in detail with reference to the accompanying drawings. However, the present invention is not limited to the disclosed embodiments and may be implemented in different forms. The embodiments are provided to complete the disclosure of the present invention and to allow those of ordinary skill in the art to fully understand the scope of the present invention, and the present invention is defined merely by the claims. The terms used herein are for illustrative purposes of the inventive concept only and should not be construed to limit the meaning or the scope of the inventive concept. As used in this specification, a singular form may, unless definitely indicating a particular case in terms of the context, include a plural form. Also, the expressions “comprise” and/or “comprising” used in this specification neither define the mentioned components, steps, operations and/or elements, nor exclude the presence or addition of one or more other different components, steps, operations and/or elements, or addition of these. As used herein, terms such as “first,” “second,” etc. are used to describe various components, but components should not be defined by these terms. Terms are used only for distinguishing one component from another component.

FIG. 1is an exploded perspective view of a battery pack according to an embodiment of the present invention,FIG. 2is a diagram showing labeling of the battery pack shown inFIG. 1, andFIG. 3is a cross-sectional view showing a cross-section cut along a line I-I′ shown inFIG. 2.

Referring toFIG. 1, a battery pack10according to an embodiment of the present invention may include a case100which includes a first case110and a second case120which are coupled to each other, a plurality of battery cells200which are received between the first case110and the second case120and are positioned in parallel with each other, and a label500which is attached on an outer surface of the case100.

The plurality of battery cells200are rechargeable secondary cells and may include, for example, lithium-ion cells. Each of the plurality of battery cells includes an electrode assembly (not shown) and a can210which receives the electrode assembly (not shown), and the electrode assembly (not shown) may be manufactured by depositing an anode plate, a cathode plate, and a separator interposed therebetween, and winding them in the form of a jelly roll.

The can210is made of a metallic material and may have a first electric charge on a surface thereof. For example, the can210may be formed of, but not limited to, aluminum or an aluminum alloy.

The plurality of battery cells200may be disposed side-by-side along one direction, and the plurality of battery cells may be connected in series or in parallel by a lead plate300. While three battery cells200are connected in series to form one battery pack10inFIG. 1, the present invention is not limited to this example. That is, the number of battery cells200forming the battery pack10or how to connect them is not particularly limited and may be various.

The plurality of battery cells200may be electrically connected with a protection circuit module400. The protection circuit module400may prevent overheat or explosion occurring due to overcharge, over-discharge, or over-current of the plurality of battery cells200connected in series or in parallel.

The protection circuit module400may include a substrate410and protection elements (not shown) mounted at a side of or inside the substrate410. The protection elements may include a safety element including passive elements such as a resistor and a condenser and an active element such as a field effect transistor (FET), or integrated circuits.

A connector420may be provided at a side of the protection circuit module400to supply power to an external electronic device. The connector420is connected with an electronic device on which the battery pack10is mounted.

Since the exterior of the battery cell200is formed by the can210having conductivity, the plurality of battery cells200disposed side-by-side have to be insulated from each other. To this end, a spacer600is disposed between adjacent battery cells200to prevent short circuit between the adjacent battery cells200.

The spacer600is formed of an insulating material such as plastic, and the length of the spacer600may be longer than that of the battery cell200.

The spacer600may be positioned between a first support112and a second support122, such that the spacer600, together with the first support112and the second support122fixes the battery cells200.

For example, both sides of the spacer600may be formed to be matched with sides of the battery cells200contacting the sides of the spacer600. For example, when the sides of the battery cells200have an outwardly convex shape, both sides of the spacer600contacting the battery cells200have a concave shape, thereby efficiently fixing the battery cells200.

A blocking portion650may be formed at one end of the spacer600. The blocking portion650may extend in a perpendicular to a longitudinal direction of the spacer600. For example, the blocking portion650may extend to the left and to the right, such that the spacer600may have an overall T-shape. The blocking portion650extending to the left and to the right may contact lower portions of the battery cells200disposed at both sides of the spacer600. A space S3for seating the blocking portion650thereon may be formed on a side of the second case120, and the blocking portion650may contact an inner side123of the second case120.

The first case110and the second case120are coupled to each other to form a space51for receiving the plurality of battery cells200and a space S2for receiving the protection circuit module400.

The first case110and the second case120may be formed by injecting an insulating plastic material. The plastic material may be, but not limited to, polyvinyl chloride (PVC), polystyrene (PS), polypropylene (PP), polycarbonate (PC), polyimide (PI), etc.

In the first case110are formed a plurality of first openings111to minimize an overall thickness of the case100, and respective one surfaces of the plurality of battery cells200are exposed by the plurality of first openings111. The first support112for supporting an edge of a top surface or bottom surface of the battery cell200are formed at an edge of each of the plurality of first openings111.

Likewise, in the second case120are formed a plurality of second openings121which expose respective another surfaces of the plurality of battery cells200, and the second support122is formed at an edge of each of the plurality of second openings121.

A sum of thicknesses of the first support112and the second support122may be equal to a thickness of the battery cell200increased when the battery cells200are fully swollen. As will be described below, a label500is attached on the first support112and the second support122which have particular thicknesses, and the battery cell200is swollen in charging/discharging. If a sum of thicknesses of the first support112and the second support122is equal to a thickness of the battery cell200increased when the battery cells200are fully swollen, a swelling space for the battery cells200is secured, such that in spite of swelling of the battery cell200, an overall external appearance of the battery pack10is not changed or remains about the same.

The first case110and the second case120may be insertedly coupled to each other by a hook structure formed along their sides.

As shown inFIG. 3, the first case110and the second case120may include a side coupling portion which forms an outwardly convex round shape. Herein, the side coupling portion means an opposite side to a region where the protection circuit module400is positioned, that is, a lower side with respect to the battery cell200.

More specifically, in the side coupling portion, the first case110includes a protrusion portion114directed toward the second case120, and the second case120may include a first fixing portion124and a second fixing portion126which form an engagement groove to allow the protrusion portion114to be insertedly coupled thereto.

The protrusion portion114includes a holding protrusion116, and a holding latch to which the holding protrusion116is engaged may be formed in the engagement groove. For example, a groove in a concave shape matched to the shape of the holding protrusion116may be formed in the second fixing portion126. Thus, the first case110and the second case120may be easily coupled in a one-touch manner.

The label500is attached to the first case110and the second case120coupled to each other. More specifically, the label500may include a first surface501attached on an outer surface of the second case120, a second surface503attached on an outer surface of the first case110, and an intermediate surface502which surrounds an outer circumferential surface of the side coupling portion. The intermediate surface503connects the first surface501and the second surface502, and is formed continuous from the first surface501and the second surface502.

FIG. 2is a diagram showing how to attach the label500, and referring toFIG. 2, first, the first surface501is attached on the second case120. While the order of attachment of the label500is not specially limited, the first surface501may be first attached on the second case120in terms of attachment efficiency because the space S2for seating the protection circuit module400thereon is further formed on the second case120and a portion for covering the space S2is further formed on the first surface501.

In the second case120are formed the plurality of second openings121through which the battery cells200are exposed, such that the first surface501is attached on the battery cells200as well as on the second case120.

Once the first surface501is attached on the second case120, the intermediate surface502is successively attached on an outer side of the side coupling portion of the first case110and the second case120.

As shown inFIG. 3, the side coupling portion of the first case110and the second case120form the outwardly convex round shape, such that the label500may be continuously attached without being bent or folded. In addition, an attached area of the label500may be maximized, such that the second support122of the second case120on which the label500is attached may have a minimum label-attached area.

The side coupling portion may form a curved surface having a predetermined curvature. When the intermediate surface502is attached to the side coupling portion, a tension is applied in the same direction as a tangent line of the curved surface formed by the side coupling portion, such that the intermediate surface502is sequentially attached on the side coupling portion while maintaining a tight state. Thus, when the side coupling portion forms the curved surface having a predetermined curvature, the tension applied to the intermediate surface502during attachment of the intermediate surface502may be maintained constant, thereby attaching the intermediate surface502while effectively inhibiting generation of air bubbles or lifting.

After completion of attachment of the intermediate surface502, the second surface503is successively attached on the first case110.

As mentioned above, the plurality of first openings111which expose the plurality of battery cells200are formed in the first case110, such that the second surface503is also attached on the battery cells200as well as on the first case110. Thus, the battery cells may be effectively fixed because their top surfaces and bottom surfaces are attached by the label500.

FIG. 4Ais an enlarged view of a portion P shown inFIG. 3, andFIG. 4Bis a diagram for comparison withFIG. 4A. Herein, inFIG. 4B, a label attached to a battery pack is attached separately on a top surface and a bottom surface, andFIG. 4Bshows an enlargement of a portion corresponding to the portion P shown inFIG. 4A. That is,FIG. 4Bshows an enlargement of a second case120′ for comparison withFIG. 4A.

Referring toFIG. 4B, a label500′ is attached on a first case (not shown) and the second case120′ positioned on both surfaces of the battery cell200, such that a minimum label-attached area for attaching the label500′ to the first case (not shown) and the second case120′ should be secured, and a region on which the label500′ is attached has to be defined.

As a result, the region on which the label500′ is attached, e.g., a second support122′ of the second case120′ needs to be formed with a long length L2to secure the minimum label-attached area. Moreover, considering injection of the second support122′ formed long, the second support122′ needs to have a predetermined thickness T2. Furthermore, to define the region on which the label500′ is attached, a step portion E has to be formed in the second case120′. When the step portion E has a thickness of T3, the thickness of the second case120′ is equal to T2+T3.

On the other hand, referring toFIGS. 3 and 4A, the first case110and the second case120have the side coupling portion which forms an outwardly convex round shape, such that the label500may be continuously attached on the case100.

That is, since the label500is attached while enclosing a side of the case100, an attached area of the label500is maximized, such that the second support122of the second case120and the first support112of the first case110on which the label500is attached may have a minimum label-attached area. The first support112and the second support122may be formed to support the battery cell200and to prevent the battery cell200from leaving the case100. Thus, both the length L1of the second support122and the thickness T1of the second support122may be reduced. Consequently, the battery pack10may have a slim structure.

As described above, according to the one or more of the above embodiments of the present invention, area and thickness of a label-attached portion of a case on which a label is attached may be minimized, allowing a slim structure of a battery pack.

While the present invention has been described with reference to the aforementioned embodiments, various modifications or changes can be made without departing from the subject matter or scope of the present invention. Therefore, the scope of the appended claims may include such modifications or changes included in the subject matter of the present invention.