Secondary battery

A secondary battery comprises an electrode assembly including a first electrode, a separator, and a second electrode alternately stacked and wound about a central axis. A first non-coating portion that is not coated with an electrode active material protrudes farther than the separator in a first direction along the central axis and a second non-coating portion that is not coated with the electrode active material protrudes farther than the separator in a second, opposite direction along the central axis. The first non-coating portion contacts a first connection part disposed on an end of a first can of the battery, and the second non-coating portion contacts a second connection part disposed on an end of a second can. At least one of the first connection part or the second connection part comprises a protrusion having a shape protruding towards the electrode assembly.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a national phase entry under 35 U.S.C. § 371 of International Application No. PCT/KR2019/012790 filed Oct. 1, 2019, which claims the benefit of the priority of Korean Patent Application No. 10-2018-0118989, filed on Oct. 5, 2018, which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The present invention relate to a secondary battery.

BACKGROUND ART

Secondary batteries are rechargeable, unlike primarily batteries, and also they are very capable of compact size and high capacity. Thus, recently, many studies on secondary batteries have been carried out. As technology development and demands for mobile devices increase, the demands for secondary batteries as energy sources are rapidly increasing.

Secondary batteries are classified into coin type cells, cylindrical type cells, prismatic type cells, and pouch type cells according to a shape of a battery case. In such a secondary battery, an electrode assembly mounted in a battery case is a chargeable and dischargeable power generating device having a structure in which an electrode and a separator are stacked.

The electrode assembly may be generally classified into a jelly-roll type electrode assembly, a stacked type electrode assembly, and a stack/folding type electrode assembly. In a jelly-roll type electrode assembly, a separator is interposed between a positive electrode and a negative electrode, each of which is provided as the form of a sheet coated with an active material, and then, the positive electrode, the separator, and the negative electrode are wound. In a stacked type electrode assembly, a plurality of positive and negative electrodes with a separator therebetween are sequentially stacked. In a stack/folding type electrode assembly, stacked type unit cells are wound together with a separation film having a long length. Among them, the jelly-roll type electrode assembly is widely used because the jelly-roll type electrode assembly has advantages in ease of manufacturing and high energy density per weight.

DISCLOSURE OF THE INVENTION

Technical Problem

One aspect of the present invention is to provide a secondary battery which has minimum resistance and improved heat dissipation characteristics.

In addition, another aspect of the present invention is to provide a secondary battery regardless of any meandering of a wound electrode when a can and the electrode are welded to each other.

Furthermore, another aspect of the present invention is to provide a secondary battery in which electrode resistance and thermal deviation are capable of being improved.

Technical Solution

A secondary battery according to an embodiment of the present invention comprises an electrode assembly in which a first electrode, a separator, and a second electrode are alternately stacked, and a can configured to accommodate the electrode assembly, wherein the first electrode is disposed on an end of the electrode assembly in one direction so that a first electrode non-coating portion that is not coated with an electrode active material protrudes more than the separator with respect to a direction of a winding center axis of the electrode assembly, the second is disposed on an end of the electrode assembly in the other direction so that a second electrode non-coating portion that is not coated with the electrode active material protrudes more than the separator with respect to the direction of the winding center axis of the electrode assembly, the can comprises a first can and a second can, the first electrode non-coating portion contacts a first connection part disposed on an end of one side of the first can, and the second electrode non-coating portion contacts a second connection part disposed on an end of the other side of the second can, and at least one of the first connection part or the second connection part comprises a protrusion connection part having a shape protruding in a direction of the electrode assembly.

Advantageous Effects

According to the present invention, the electrode of the wound electrode assembly may be directly connected to the can without a connection member to minimize resistance and improve the heat dissipation characteristics.

Also, according to the present invention, the protrusion connection part protruding toward the electrode assembly may be formed on the can so that the welding between the electrode non-coating portion of the electrode assembly and the can is performed regardless of any meandering of the wound electrode.

Furthermore, according to the present invention, the welding position and the welding pattern between the can and the electrode non-coating portion may be uniformly formed to improve the electrode resistance and the thermal deviation.

MODE FOR CARRYING OUT THE INVENTION

The objectives, specific advantages, and novel features of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. It should be noted that the reference numerals are added to the components of the drawings in the present specification with consistent numerals as much as possible, even if they are illustrated in other drawings. Also, the present invention may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. In the following description of the present invention, the detailed descriptions of related arts which may unnecessarily obscure the gist of the present invention will be omitted.

FIG.1is a perspective view of a secondary battery according to a first embodiment of the present invention, and

FIG.2is a cross-sectional view illustrating an example of the secondary battery according to the first embodiment of the present invention.

Referring toFIGS.1and2, a secondary battery100according to an embodiment of the present invention comprises an electrode assembly110, a can120comprising a first can121and a second can122, which accommodate the electrode assembly110therein, and an insulator123insulating an overlapping portion between the first can121and the second can122.

FIG.3is an exploded perspective view of the secondary battery according to the first embodiment of the present invention, andFIG.4is a conceptual perspective view of an electrode assembly in the secondary battery according to the first embodiment of the present invention.

Hereinafter, the secondary battery according to an embodiment of the present invention will be described in more detail with reference toFIGS.1to7.

Referring toFIGS.2to4, the electrode assembly110may be a chargeable and dischargeable power generation element and have a structure in which the electrode113and the separator114are combined and alternately stacked with each other. Here, the electrode assembly110may have a wound shape.

The electrode113may comprise the first electrode111and the second electrode112. Also, the separator114may separate the first electrode111from the second electrode112to insulate the first and second electrodes111and112from each other. Here, each of the first electrode111and the second electrode may be provided in the form of a sheet and then be wound together with the separator114so as to be formed in a jelly roll type. Here, the electrode assembly110may be wound, for example, in a cylindrical shape.

Although the first electrode111is provided as a positive electrode, and the second electrode112is provided as a negative electrode, the present invention is not limited thereto. For example, the first electrode111may be provided as a negative electrode, and the second electrode112may be provided as a positive electrode.

The first electrode111may comprise a first electrode collector111aand a first electrode active material111bapplied on the first electrode collector111a. Also, the first electrode111may comprise a first electrode non-coating portion111cthat is not coated with the first electrode active material111b. Here, the first electrode non-coating portion111cmay be disposed on an end of the electrode assembly in one direction S1to protrude farther than the separator114with respect to a direction of a winding center axis S of the electrode assembly110.

Also, the first electrode111may be provided as, for example, a negative electrode and comprise a negative electrode collector (not shown) and a negative electrode active material (not shown) applied on the negative electrode collector. Also, a negative electrode non-coating portion that is not coated with the negative electrode active material may be formed on the first electrode111.

For example, the negative electrode collector may be provided as foil made of a copper (Cu) or nickel (Ni) material. The negative electrode active material may comprise synthetic graphite, lithium a metal, a lithium alloy, carbon, petroleum coke, activated carbon, graphite, a silicon compound, a tin compound, a titanium compound, or an alloy thereof. Here, the negative electrode active material may further comprise, for example, non-graphite-based SiO (silica) or SiC (silicon carbide).

The second electrode112may comprise a second electrode collector112aand a second electrode active material112bapplied on the second electrode collector112a. Also, the second electrode112may comprise a second electrode non-coating portion112cthat is not coated with the second electrode active material112b. Here, the second electrode non-coating portion112cmay be disposed on an end of the electrode assembly in the other direction S2to protrude farther than the separator14with respect to the direction of the winding center axis S of the electrode assembly110.

Here, the second electrode112may be provided as, for example, a positive electrode and comprise a positive electrode collector (not shown) and a positive electrode active material (not shown) applied on the positive electrode collector. Also, a positive electrode non-coating portion that is not coated with the positive electrode active material may be formed on the second electrode112.

For example, the positive electrode collector may be provided as foil made of an aluminum material, and the positive electrode active material may be made of lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium iron phosphate, or a compound or mixture thereof containing at least one or more of the above-described materials.

The separator114may be made of an insulating material, and the first electrode111, the separator114, and the second electrode112may be alternately stacked. Here, the separator114may be disposed between the first electrode111and the second electrode on outer surfaces of the first electrode111and the second electrode112. Here, the separator114may be disposed at the outermost side in a width direction when the electrode assembly110is wound.

Also, the separator114may be made of a flexible material. Here, the separator114may be made of, for example, a polyolefin-based resin film such as polyethylene or polypropylene having micropores.

The can120may be provided with an accommodation part that accommodates the electrode assembly110therein and comprise a first can121and a second can122, which have cylindrical shapes opened in a direction facing each other.

Also, the can120may be made of a conductive material. Here, the can120may comprise a metal. For example, the first can121may be made of aluminum, and the second can122may be made of steel. For another example, the first can121may be made of steel, and the second can122may be made of aluminum. Particularly, for example, the can made of aluminum may be connected to the positive electrode, and the can made of steel may be connected to the negative electrode.

Also, the first can121may be electrically connected to the first electrode111, and the second can122may be electrically connected to the second electrode112. Here, the first can121may directly contact an end of the first electrode111to form a first electrode terminal, and the second can122may directly contact an end of the second electrode112to form a second electrode terminal.

In one example, when the first electrode is the positive electrode, the first can121contacting the end of the first electrode111may form the positive electrode terminal. Here, the first can121may be made of aluminum. Also, in this case, the second electrode may be the negative electrode, and the second can122contacting the end of the second electrode112may form the negative electrode terminal. Here, the second can122may be made of steel.

Also, the first can121and the second can122may have shapes corresponding to each other.

Also, the first can121and the second can122may have cylindrical shapes opened in a direction facing each other. The first can121may have an inner circumferential surface greater than an outer circumferential surface of the second can122so that the second can is inserted into the first can121.

The first can121may have a first opening121dopened in one end in the direction S2, and the second can122has a second opening (not shown) opened in the other end in the direction S1. In this case, the second connection part122adisposed in the direction S2of the second can122may be disposed outside the first can121even after the second can122is inserted into the first can121.

Furthermore, the first electrode111may have one end connected to the first connection part121a, and the second electrode122may have one end connected to the second connection part122a. Here, for example, the first electrode non-coating portion111cof the first electrode111may directly contact the first connection part121a, and the second electrode non-coating portion112cof the second electrode112may directly contact the second portion122a.

FIG.5is a cutaway perspective view illustrating a portion of the first can in the secondary battery according to the first embodiment of the present invention, andFIG.6is an enlarged cutaway perspective view illustrating a portion of the secondary battery according to the first embodiment of the present invention.

Referring toFIGS.2,5, and6, for example, the protrusion connection part may be formed on at least one of the first connection part121aor the second connection part122ato protrude in the direction of the electrode assembly110.

In more detail, a first protrusion connection part121bprotruding in the direction of the electrode assembly110may be disposed on the first connection part121aof the first can121, and thus, the first electrode non-coating portion111cmay be connected to the first protrusion connection part121b. Also, a second protrusion connection part (not shown) protruding in the direction of the electrode assembly110may be disposed on the second connection part122a, and the second electrode non-coating portion112cmay be connected to the second protrusion connection part. Here, the second protrusion connection part may have a shape corresponding to that of the first protrusion connection part121b.

Also, each of the first protrusion connection part121band the second protrusion connection part may have a shape that is bent and recessed in the direction of the electrode assembly110. A concave portion is formed in an outer surface of the first can121, and a convex portion may be formed on an inner surface of the first can121.

Furthermore, the first electrode non-coating portion111cmay be welded and fixed to the first protrusion connection part121b, and the second electrode non-coating portion112cmay be welded and fixed to the second protrusion connection part.

Also, the first protrusion connection part121bmay be formed on the first connection part121ain the form of a plurality of circles having different diameters in the plan view, with a first protrusion121b-1, a second protrusion121b-2, and a third protrusion121b-3being sequentially formed from an outer portion of the first connection part121atowards a central direction.

The second protrusion connection part (not shown) having a shape corresponding to that of the first protrusion connection part121bformed on the first connection part121aof the first can121may also be formed on the second connection part of the second can122. Here, the second electrode non-coating portion112cof the second electrode112may be welded and connected to the second protrusion connection part formed on the second connection part122a.

Referring toFIG.2, the insulator123may comprise an insulating material to insulate an overlapping portion between the first can121and the second can122.

Furthermore, the insulator123may comprise an insulating polymer. In this case, the insulating polymer may be, for example, a polymer.

Referring toFIGS.2and6, in the secondary battery100having the above-described configuration according to an embodiment of the present invention, the first electrode111and the second electrode112of the wound electrode assembly110may be directly connected to the first can121and the second can122without a connection member, thereby minimizing resistance and improving heat dissipation characteristics. Also, the protrusion connection part protruding in the direction of the electrode assembly110may be formed on the can120so that the first electrode non-coating portion111cand the second electrode non-coating portion112cof the wound electrode assembly110may be welded to the first can121and the second can122regardless of meandering of the wound first and second electrodes111and112(the meandering means that the electrode was not uniformly rolled but rather rolled so as to be inclined when being wound). That is, the meandering may occur somewhat when the electrode is wound. If the meandering occurs, when the electrode non-coating portion is welded to the can, a portion at which the electrode non-coating portion does not contact the can may occur. According to the present invention, since the protrusion connection part is formed on the can, even when the meandering partially occurs during the winding of the electrode, the electrode non-coating portion and the can may well contact each other. Thus, sufficient welding may be possible.FIG.6illustrates a state in which the first electrode non-coating portion is bent at the portion at which the protrusion connection portion is formed so as to well contact the inner surface of the can.

Hereinafter, a secondary battery according to another embodiment will be described.

FIG.7is a perspective view of a secondary battery according to a second embodiment of the present invention, andFIG.8is a cross-sectional view illustrating an example of the secondary battery according to the second embodiment of the present invention.

Referring toFIGS.7and8, a secondary battery200according to another embodiment of the present invention comprises an electrode assembly210, a can220comprising a first can221and a second can222, which accommodate the electrode assembly210therein, and an insulator223insulating an overlapping portion between the first can221and the second can222.

The secondary battery200according to another embodiment of the present invention is different from the secondary battery according to the foregoing embodiment in that matters for a welding pattern configuration for welding between the can220and the electrode213are further provided. Thus, contents of this embodiment, which are duplicated with those according to the forgoing embodiment, will be briefly described, and also, differences therebetween will be mainly described.

FIG.9is a plan view illustrating an example of a state in which the first electrode is spread before being wound in the secondary battery according to the second embodiment of the present invention.

In more detail, referring toFIGS.8and9, in the secondary battery200according to another embodiment of the present invention, the electrode assembly210forms a structure in which the electrodes213and a separator214are alternately stacked. Here, the electrode assembly210may have a wound shape.

The electrode213may comprise the first electrode211and the second electrode212.

The first electrode211may comprise a first electrode collector211aand a first electrode active material211bapplied on the first electrode collector211a. Also, the first electrode211may comprises a first electrode non-coating portion211cthat is not coated with the first electrode active material211b.

The second electrode212may comprise a second electrode collector212aand a second electrode active material212bapplied on the second electrode collector212a. Also, the second electrode212may comprises a second electrode non-coating portion212cthat is not coated with the second electrode active material212b.

FIG.10is an enlarged cutaway perspective view illustrating a portion of the secondary battery according to the second embodiment of the present invention, andFIG.11is a plan view of the secondary battery according to the second embodiment of the present invention. Also,FIG.12is a plan view illustrating a portion of a first case in the secondary battery according to the second embodiment of the present invention, andFIG.13is a conceptual view illustrating an example of a welding pattern in the secondary battery according to the second embodiment of the present invention.

Referring toFIGS.8and10, the can220may be provided with an accommodation part that accommodates the electrode assembly210therein and comprises a first can221and a second can222, which have cylindrical shapes opened in a direction facing each other.

Here, the first can221may be electrically connected to the first electrode211, and the second can222may be electrically connected to the second electrode212.

A first protrusion connection part221bprotruding in a direction of the electrode assembly210may be disposed on a first connection part221aof the first can221, and thus, the first electrode non-coating portion211cmay be connected to the first protrusion connection part221b. Also, a second protrusion connection part (not shown) protruding in the direction of the electrode assembly210may be disposed on the second connection part222a, and the second electrode non-coating portion212cmay be connected to the second protrusion connection part.

Each of the first protrusion connection part221band the second protrusion connection part may have a shape that is bent and recessed in the direction of the electrode assembly210. A concave portion is formed in an outer surface of the first can221, and a convex portion may be formed on an inner surface of the first can221.

The first electrode non-coating portion211cmay be welded and fixed to the first protrusion connection portion221b, and the second electrode non-coating portion212cmay be welded and fixed to the second protrusion connection portion.

Referring toFIGS.9to11, the first protrusion connection part221bare formed on the first connection part221ain the form of a plurality of circles having different diameters in the plan view, with a first protrusion221b-1, a second protrusion221b-2, and a third protrusion221b-3being sequentially formed from an outer portion O of the first connection part221atowards a direction of a winding center portion S.

Also, a distance between the first protrusion221b-1and the second protrusion221b-2may be less than a distance between the second protrusion221b-2and the third protrusion221b-3.

Here, three portions of a first electrode connection part211d, which are spaced a predetermined distance from each other on the first electrode non-coating portion211cin a longitudinal direction L of the first electrode211, may be connected to the first protrusion221b-1, the second protrusion221b-2, and the third protrusion221b-3, respectively. Particularly, the first electrode connection part211dmay comprise a first welding portion211d-1, a second welding portion211d-2, and a third welding portion211d-3, which are three portions spaced a predetermined distance from each other in the longitudinal direction L, and the first welding portion211d-1, the second welding portion211d-2, and the third welding portion211d-3may be connected to the first protrusion221b-1, the second protrusion221b-2, and the third protrusion221b-3, respectively.

Also, when the first electrode connection part211dis wound in the longitudinal direction L of the first electrode211, the first welding portion211d-1, the second welding portion211d-2, and the third welding portion211d-3may be sequentially disposed from an outer portion O of the first electrode211towards the winding center portion S of the first electrode211so as to be respectively welded and fixed to the first protrusion221b-1, the second protrusion221b-2, and the third protrusion221b-3.

Also, a moving path P of charges and heat in the first electrode211may be directed toward the first welding portion211d-1, the second welding portion211d-2, and the third welding portion211d-3. Here, the first electrode211in the longitudinal direction L may have, for example, a length of 3,780 mm. Here, for example, the welded portion of the first welding portion211d-1and the first protrusion221b-1may be disposed at a position of the wound electrode assembly110, which is spaced a distance of 10.3 mm from the winding center portion S, in the plan view; the welded portion of the second welding portion211d-2and the second protrusion221b-2is disposed at a position of the wound electrode assembly110, which is spaced a distance of 16.7 mm from the winding center portion S, in the plan view; and the welded portion of the third welding portion211d-3and the third protrusion221b-3may be disposed at a position of the wound electrode assembly110, which is spaced a distance of 21.3 mm from the winding center portion S, in the plan view.

Furthermore, the first electrode211may comprise a first section S1, a second section S2, and a third section S3, which are equally divided into three sections in the longitudinal direction L of the first electrode211, and the first welding portion211d-1, the second welding portion211d-2, and the third welding portion211d-3may be disposed at central portions of the first section S1, the second section S2, and the third section S3, respectively. For example, the first section S1, the second section S2, and the third section S3may have the same length of 1260 mm.

Referring toFIG.9, which illustrates a spread state of the first electrode211before being wound, a distance d1between the first welding portion211d-1and the second welding portion211d-2may be the same as a distance d2between the second welding portion211d-2and the third welding portion211d-3. Here, a welding length w1of the first welding portion211d-1, a welding length w2of the second welding portion211d-2, and a welding length w3of the third welding portion211d-3may be the same. Here, the welding length w1of the first welding portion211d-1, the welding length w2of the second welding portion211d-2, and the welding length w3of the third welding portion211d-3may be the same, for example, 200 mm to 300 mm.

When equally formed as described above, charges may be balanced and smoothly move, or heat may be balanced and smoothly transferred.

Referring toFIGS.9to13, a welding pattern A of the first welding portion211d-1and the first protrusion221b-1may be formed in a straight shape, a welding pattern B of the second welding portion211d-2and the second protrusion221b-2may be formed in a zigzag shape, a welding pattern C of the third welding portion211d-3and the third protrusion221b-3may be formed in a zigzag shape having a width greater than that of the zigzag-shaped welding pattern B of the second welding portion211d-2and the second protrusion221b-2. For reference, referring toFIGS.12and13, which illustrate partial enlarged views, although the welding patterns A, B, and C have the straight shape and the zigzag shape, the present invention is not limited thereto. For example, referring toFIG.11, which illustrates an entire plan view, the welding patterns A, B, and C may have a circular shape as a whole. That is, the welding pattern A may form a circle in the straight shape, and the welding pattern B and the welding pattern C may form a circle in the zigzag shape.

As a result, the first welding portion211d-1, the second welding portion211d-2, and the third welding portion211d-3of the first electrode connection part211dmay be fixed with a uniform welding area to the first protrusion221b-1, the second protrusion221b-2, and the third protrusion221b-3of the first protrusion connection part, respectively. Thus, the uniform welding area may be provided to prevent electrode resistance and thermal deviation from occurring.

In more detail, in the plan view of the first connection part221a, the welding pattern A of the first welding portion211d-1and the first protrusion221b-1may be disposed on the outer portion O to form the largest circle, the welding pattern B of the second welding portion211d-2and the second protrusion221b-2may form a circle smaller than the circle formed by the first welding portion211d-1and the first protrusion221b-1, and the welding pattern C of the third welding portion211d-3and the third protrusion221b-3may be disposed at the winding center portion S in the plane to form the smallest circle. As a result, the lengths of the welding pattern may be different from each other. Thus, the widths of the welding patterns may be differently provided to correspond to the different lengths so that the uniform welding area is provided to prevent electrode resistance and thermal deviation from occurring due to the non-uniform welding areas.

For reference, although the welding length w1of the first welding portion211d-1, the welding length w2of the second welding portion211d-2, and the welding length w3of the third welding portion211d-3are the same in the first electrode211, if the first welding portion211d-1is disposed at the outermost side, for example, wound once when the first electrode211is wound, the second welding portion211d-2may be wound twice, and the third welding portion211d-3may be wound three times. Here, when the second welding portion211d-2and the third welding portion211d-3are welded by a width of one layer of the first welding portion211d-1, which is wound once, the welding area may be non-uniform. Thus, when the second welding portion211d-2is welded, the width of the welding pattern B has to be formed to be wider than the width of the welding pattern A when the first welding portion211d-1is welded so that the first welding portion211d-1and the second welding portion211d-2actually have the same welding area. For this purpose, the width of the welding pattern C for welding the third welding portion211d-3may be wider than the welding pattern B for welding the second welding portion211d-2to provide a uniform welding area, thereby preventing the electrode resistance and the thermal deviation from occurring.

For example, the welding pattern C of the third welding portion211d-3and the third protrusion221b-3may have a zigzag shape having a width that is twice or more than that of the welding pattern B of the second welding portion211d-2and the second protrusion221b-2.

For example, the zigzag-shaped welding pattern B of the second welding portion211d-2and the second protrusion221b-2may have an angle α of 120° to 140°, which is bent in the zigzag shape, and the zigzag-shaped welding pattern C of the third welding portion211d-3and the third protrusion221b-3may have an angle β of 80° to 100°, which is bent in the zigzag shape. As a result, if the numerical limitation conditions of the welding pattern are satisfied, the first welding portion211d-1, the second welding portion211d-2, and the third welding portion211d-3may be welded with a uniform welding area to the first protrusion221b-1, the second protrusion221b-2, and the third protrusion221b-3of the first protrusion connection part221b, respectively.

The second protrusion connection part (not shown) having a shape corresponding to that of the first protrusion connection part221bformed on the first connection part221aof the first can221may also be formed on the second connection part of the second can222. Here, the second electrode support portion212cof the second electrode212may be welded and connected to the second protrusion formed on the second connection part222awith the same welding pattern as the shape in which the first electrode non-coating portion211cof the first electrode211is welded to the first protrusion connection part221b.

Referring toFIGS.8,10, and12, in the secondary battery200having the configuration as described above according to the second embodiment of the present invention, the welding position and the welding pattern between the first and second cans221and222and the first and second electrode non-coating portions211cand212cmay be uniform to improve the electrode resistance and the thermal deviation.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the scope of the present invention is not limited to the secondary battery according to such exemplary embodiments. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

Furthermore, the scope of protection of the present invention will be clarified by the appended claims.