Secondary battery

Abstract

A secondary battery includes an electrode assembly, a pouch accommodating the electrode assembly, and a cover tape attached to the pouch so as to at least partially cover at least two surfaces of the pouch. The cover tape includes a fixed region attached to the first surface of the pouch, a dot region attached to the second surface of the pouch, and an adhesive on the fixed region and the dot region, and the adhesive has different adhesive forces.

Description

Technical Field

[0001] The embodiments of this disclosure relate to secondary batteries. Background Technology

[0002] Unlike primary batteries, which are non-rechargeable, secondary batteries are rechargeable and dischargeable. Low-capacity secondary batteries can be used in portable small electronic devices such as smartphones, feature phones, laptops, digital cameras, and camcorders, while high-capacity secondary batteries are widely used in hybrid vehicles, electric vehicles, and other applications as power sources for driving motors and as batteries for energy storage. Such secondary batteries include electrode assemblies (which include positive and negative electrodes), a casing housing the electrode assemblies, and electrode terminals connected to the electrode assemblies.

[0003] The information disclosed in this section is provided to enhance the understanding of the background art of this disclosure, and therefore may include information that does not form related art. Utility Model Content

[0004] According to one aspect of the embodiments of this disclosure, a secondary battery is provided that is capable of preventing (preventing or substantially preventing) exposure of the adhesive of the cover strip covering the outer surface of the battery cell.

[0005] However, the aspects and purposes of this disclosure are not limited to those described above, and other aspects and purposes of this disclosure will be clearly understood by those skilled in the art from the following description.

[0006] According to one or more embodiments, a secondary battery includes an electrode assembly, a bag housing the electrode assembly, and a cover strip attached to the bag to at least partially cover at least two surfaces of the bag, wherein the cover strip includes a fixing area attached to a first surface of the bag, a dotted area attached to a second surface of the bag, and an adhesive on the fixing area and the dotted area, and the adhesive has different adhesive forces.

[0007] In one or more embodiments, the fixing area of ​​the cover strap may cover the side surface of the bag, and the dotted area of ​​the cover strap may cover at least a portion of the upper surface of the bag.

[0008] In one or more embodiments, the adhesive on the dot area may have a smaller adhesive force than the adhesive on the fixed area.

[0009] In one or more embodiments, the cover tape may include a base region that is attached to the lower surface of the bag and has a first adhesive force.

[0010] In one or more embodiments, the cover tape may include: a first dot area extending from a side surface of the base area and having a second adhesive force; a second dot area on an edge of a portion of the first dot area and having a first adhesive force; and a first fixing area on an edge of the second dot area and having a third adhesive force.

[0011] In one or more embodiments, the cover tape may include: a base region attached to the lower surface of the bag and having a first adhesive force; a second fixing region extending from the opposite side surface of the base region and having a third adhesive force; and a third point region extending along the outside of the second fixing region and having a second adhesive force.

[0012] In one or more embodiments, the second adhesive force may be less than the first adhesive force.

[0013] In one or more embodiments, the third adhesive force may be greater than the first adhesive force.

[0014] In one or more embodiments, the first adhesive force may be 0.20 to 0.50 kgf / 25 mm.

[0015] In one or more embodiments, the second adhesive force may be from 0.05 to 0.25 kgf / 25 mm.

[0016] In one or more embodiments, the third adhesive force may be from 1.10 to 1.40 kgf / 25 mm.

[0017] In one or more embodiments, the cover tape may also include a termination area at the end of the first fixing area or the third point area and no adhesive is applied to the termination area.

[0018] In one or more embodiments, the termination region may be at the outermost edge of the first fixed region or the third point region.

[0019] In one or more embodiments, the termination region may have a thickness different from the thickness of the base material of the cover strip.

[0020] In one or more embodiments, the termination area may be thicker than the base material of the cap tape and may contact the upper surface of the bag. Attached Figure Description

[0021] Some exemplary embodiments are illustrated in conjunction with the accompanying drawings, and the technical aspects and concepts of this disclosure are further illustrated in conjunction with the following detailed description of some embodiments; however, this disclosure should not be construed as limited to what is shown in the drawings.

[0022] Figure 1 This is an exploded perspective view of a pouch cell-type battery cell constituting a secondary battery according to an embodiment.

[0023] Figure 2 This is a perspective view of a secondary battery according to an embodiment;

[0024] Figure 3 yes Figure 2 An enlarged view of region "A" in the image;

[0025] Figure 4 This is a plan view of the cover strip of the secondary battery according to the embodiment; and

[0026] Figure 5 Is in Figure 2 The side view when viewed from the direction "B". Detailed Implementation

[0027] In this document, some embodiments will be described in more detail with reference to the accompanying drawings. It should be understood that the terms or words used in the specification and appended claims should not be construed as limited to their general or dictionary meanings, but should be interpreted based on the principle that inventors are allowed to define appropriate terms for best interpretation, and based on the meaning and concept of the technical concept according to this disclosure. The embodiments described in this specification and the constructions shown in the drawings are provided as some exemplary embodiments and do not necessarily represent the entire technical concept of this disclosure. Therefore, it should be understood that various alternative equivalents and modifications may be possible at the time of filing this application. As used herein, the terms “comprising” (or “including”) and / or “comprising…” (or “including…”) are intended to indicate the presence of the stated drawings, figures, steps, operations, components, elements, and / or groups thereof, and do not exclude the presence or addition of one or more other drawings, figures, steps, operations, components, elements, and / or groups. Furthermore, when describing embodiments, the use of “may” may refer to “one or more embodiments”.

[0028] The accompanying drawings may not be to scale, and some components may be exaggerated in size to aid in understanding this disclosure. In various embodiments, the same components may be represented by the same reference numerals.

[0029] The reference to "equivalent" or "identical" for two components means that they can be equivalent or substantially equivalent, or identical or substantially identical. Therefore, substantially identical can include what is considered in the art to be a low deviation (such as less than 5%). If the parameters are uniform in a given region, this can mean that the parameters are uniform from an average perspective.

[0030] Although terms such as "first," "second," etc., can be used to describe various components, components are not limited by these terms. These terms are used to distinguish one component from another, and the first component can be referred to as the second component unless otherwise specified.

[0031] Throughout this instruction manual, each component may be singular or plural unless otherwise stated.

[0032] If any construction is positioned "above" (or "below") or "on" (or "under") a component, this can mean not only that the construction is positioned adjacent to the upper (or lower) surface of the component, but also that another construction can be inserted between the component and the construction positioned on (or below) the component.

[0033] It should also be understood that if a component is described as being “connected,” “joined,” or “linked” to another component, the components may be directly connected or linked to each other, one or more other components may be “inserted” between the components, or the components may be “connected,” “joined,” or “linked” to each other via one or more other components. When a component is described as being electrically joined to another component, the component may be directly joined to the other component or indirectly joined to the other component via one or more intermediary components.

[0034] Throughout this specification, references to “A and / or B” mean A, B, or A and B, unless otherwise stated. The term “and / or” means all or any combination of multiple related listed items. References to “C through D” mean C or higher and D or lower, unless otherwise stated.

[0035] Here, the secondary battery according to the embodiment will be described in more detail.

[0036] Figure 1 This is an exploded perspective view of a pouch cell-type battery cell constituting a secondary battery according to an embodiment.

[0037] In an embodiment, the battery cell 100 may be configured as a pouch cell and may include an electrode assembly, a first current collector, a first terminal, a second current collector, a second terminal, a casing and a cover assembly.

[0038] A single battery cell may include an electrode assembly 110 and a pouch 130 for housing the electrode assembly 110.

[0039] The electrode assembly 110 may include a negative electrode plate 112 as a first electrode plate, a positive electrode plate 114 as a second electrode plate, and a diaphragm 116 inserted between the negative electrode plate 112 and the positive electrode plate 114. The negative electrode plate 112 may be provided with a negative electrode tab 112a electrically connected to an uncoated area of ​​the negative electrode, and the positive electrode plate 114 may be provided with a positive electrode tab 114a electrically connected to an uncoated area of ​​the positive electrode. In an embodiment, the negative electrode tab 112a and the positive electrode tab 114a may be soldered to negative electrode leads 152 and positive electrode leads 154 of external terminals for electrical connection to the outside. In an embodiment, a tab membrane 156 for insulation from the bag 130 may be attached to the negative electrode leads 152 and the positive electrode leads 154.

[0040] With the electrode assembly 110 contained, the bag 130 can be sealed by providing contact between sealing portions 132 at its edges. The seal can be achieved using a connecting piece membrane 156 disposed between the sealing portions 132. Figure 1 As shown, the terminal block membrane 156 attached to each of the negative electrode terminal block 112a and the positive electrode terminal block 114a can be defined as a "separate terminal block membrane" (the sealing structure can be defined as a separate sealing structure).

[0041] The sealing portion 132 of the bag 130 can be made of a heat-fusible material, and a seal can be achieved by adhering the heat-fusible layers to each other. Because heat-fusible materials generally have weak adhesion to metals, a thin-film connector film 156 can be attached to the connector and fused to the bag 130. However, in a separate sealing structure, the connector film 156 is attached and welded to each connector and then heat-fused to the bag 130, resulting in a deterioration in processability and productivity.

[0042] Figure 2 This is a perspective view of a secondary battery according to an embodiment; Figure 3 yes Figure 2 An enlarged view of region "A" in the image.

[0043] Reference Figure 2 and Figure 3 The secondary battery 10 according to the embodiment may include a battery cell 100 and a cover strip 200 bonded to the outer surface of the battery cell 100.

[0044] The above has been referenced Figure 1 The basic structure of the battery cell 100 is described. The negative electrode lead 152 and positive electrode lead 154 of the battery cell 100 can be exposed outside the sealed portion 132 of the pouch 130 and can be connected to the lead terminal piece 160, such as... Figure 2As shown in the diagram, the battery cell 100 can be connected to an external device, such as a charging / discharging device, via lead connectors 160.

[0045] The cover tape 200 can protect and insulate the pouch 130 of the battery cell 100. The cover tape 200 can be attached to the outside of the battery cell 100, such as the outside of the pouch 130. The cover tape 200 can be attached to the battery cell 100 to cover at least one surface of the battery cell 100.

[0046] For example, the cover strip 200 may be attached to two side surfaces of the battery cell 100, which are adjacent to the side surface of the battery cell 100 on which the lead terminal piece 160 is formed. In an embodiment, the cover strip 200 may include wings formed on its sides to enhance adhesion to the battery cell 100.

[0047] The adhesive formed on the inner surface of the cover strip for attaching the cover strip may be exposed during the attachment of the cover strip or during the use of the secondary battery. If the adhesive is exposed, the assemblability and productivity of the secondary battery may deteriorate, foreign matter may adhere to it, or the adhesive may enter external devices and potentially cause defects in the external devices.

[0048] However, according to the embodiment, the cover strip 200 for the secondary battery 10 can avoid the above-mentioned problems by preventing (preventing or substantially preventing) the exposure of adhesive (e.g., adhesive located on its edges).

[0049] Here, the construction of the cover strip 200 for the secondary battery 10 according to an embodiment will be described.

[0050] Figure 4 This is a plan view of the cover strip of the secondary battery according to the embodiment.

[0051] Reference Figure 4 The cover strip 200 may include a base region 210 as the base of its structure (e.g., the entire structure). The base region 210 may be adhered to the lower surface of the battery cell 100 by a first adhesive force.

[0052] The cover strip 200 may also include a first point area 220, a second point area 230, and a first fixing area 240, wherein the first point area 220 is coupled to the base area 210 and thus disposed on one side of the base area 210. Figure 4The first fixing area 230 is formed on the left side of the first fixing area 220 and has a second adhesive force less than the first adhesive force. The second fixing area 240 is formed further outward than the first fixing area 220 and has a first adhesive force. The first fixing area 240 is formed on the edge of the second fixing area 230 and has a third adhesive force greater than the first adhesive force. The cover tape 200 may also include a termination area 250, which is formed on the edge of the first fixing area 240 and has no adhesive thereon.

[0053] The cover strip 200 may also include a second fixing region 260 and a third fixing region 270, the second fixing region 260 being coupled to the base region 210, thereby being disposed on the opposite side of the base region 210. Figure 4 The third point area 270 is formed on the outside of the second fixing area and has a second adhesive force. The cover tape 200 may also include a termination area 280, which is formed on the edge of the third point area 270 and has no adhesive thereon.

[0054] In one embodiment, the base region 210 may be attached to the entire surface of the battery cell 100, such as the lower surface of the battery cell 100. The adhesive formed on the inner surface of the base region 210 may have a first adhesive force, and in one embodiment, the first adhesive force may be 0.20 to 0.50 kgf / 25 mm. In one embodiment, the base region 210 may protect the entire lower surface of the battery cell 100 and may hold the cover strap 200 in place.

[0055] The first dot region 220 can be bonded to the left side of the base region 210, and the adhesive formed on the inner surface of the first dot region 220 can have a second adhesive force less than the first adhesive force. During the manufacturing process of the adhesive, the dot size of the adhesive can be designed such that its adhesive force corresponds to a second adhesive force less than the first adhesive force. For example, the second adhesive force can be 0.05 to 0.25 kgf / 25 mm. In embodiments, although the range of the second adhesive force partially overlaps with the range of the first adhesive force, the second adhesive force can be less than the first adhesive force during the manufacturing of the cover tape 200. For example, the first dot region 220 can be attached to the battery cell 100 with an adhesive force less than that used to attach the base region 210 to the battery cell 100.

[0056] The second point region 230 may be formed further outward than the first point region 220 and may have a first adhesive force. The second point region 230 may be formed to cover the side surface of the battery cell 100 and may be bent to also cover a portion of the upper surface of the battery cell 100. For example, the second point region 230 may be attached to the outer surface of the battery cell 100 with a greater adhesive force than the first point region 220 is used to attach to the battery cell 100.

[0057] The first fixing region 240 may be formed on the edge of the second fixing region 230 and may have a third adhesive force. For example, the third adhesive force may be 1.10 to 1.40 kgf / 25 mm. Because the first fixing region 240 is attached to the battery cell 100 with maximum adhesive force at the outermost edge of the cover strip 200, the bonding shape and position of the cover strip 200 can be maintained. In an embodiment, the first fixing region 240 may be provided with a wing 241 at its end. The wing 241 may be attached to a side surface of the battery cell 100 opposite to the side surface of the battery cell 100 on which the lead terminal piece 160 is formed.

[0058] The termination area 250 may be formed on the edge of the first fixing area 240 and may be free of adhesive. Because the termination area 250 is free of adhesive, it can receive adhesive even if the adhesive on the first fixing area 240 leaks from it due to the pressure applied to it during the attachment process. Therefore, it is possible to prevent or substantially prevent adhesive from being exposed to the outside of the cover tape 200.

[0059] The second fixing region 260 can be attached to the right side of the base region 210, and the adhesive formed on the inner surface of the second fixing region 260 can have a third adhesive force. The second fixing region 260 can be stably attached to the right surface of the battery cell 100 using an adhesive with high adhesive strength. In an embodiment, the second fixing region 260 is attached to the entire right surface of the battery cell 100 in the longitudinal direction of the battery cell 100, so that the attachment area can be large. The second fixing region 260 can be firmly attached to the battery cell 100 due to its adhesive with relatively strong third adhesive strength. In an embodiment, the second fixing region 260 can be provided with a wing 261 at its end. The wing 261 can be attached to the side surface of the battery cell 100 opposite to the side surface of the battery cell 100 on which the lead terminal piece 160 is formed.

[0060] The third point region 270 can be formed on the outer side of the second fixing region, and its adhesive can have a second adhesive force. During the manufacturing process of the adhesive, the point size of the adhesive can be designed such that its adhesive force corresponds to a second adhesive force less than the first adhesive force. In an embodiment, the third point region 270 is formed to extend along the second fixing region 260 in the longitudinal direction of the battery cell 100, and even if the adhesive in the second fixing region 260 moves, the adhesive can be received within the second fixing region 260 without being exposed. In an embodiment, the adhesive in the third point region 270 has a second adhesive force less than the first adhesive force, thereby reducing the exposure of the adhesive in the third point region 270 to the outside during the manufacturing process.

[0061] In one embodiment, a termination region 280 without adhesive may be further provided on the edge of the third point region 270. In another embodiment, the termination region 280 has no adhesive on the inner surface of the base material of the strip, so that even if adhesive leaks from the third point region 270 during the manufacturing process, it can be received within the termination region 280. Therefore, adhesive exposure to the outside can be prevented or substantially prevented.

[0062] Although termination regions 250 and 280 are described as non-adhesive regions on which no adhesive is present, in one or more embodiments, termination regions 250 and 280 can be used as dams against adhesive by increasing the thickness of the base material of termination regions 250 and 280. In embodiments, termination regions 250 and 280 can prevent or substantially prevent the adhesive from leaking from the first fixing region 240 and the third point region 270, and thus can prevent or substantially prevent the exposure of the adhesive.

[0063] Here, the construction of the cover strip being bonded to the battery cell in the structure of the secondary battery according to the embodiment will be described.

[0064] Figure 5 Is in Figure 2 Side view when viewed from the direction "B" shown.

[0065] Figure 5 The structure shown is viewed in direction "B" with the cover strip 200 attached to the battery cell 100. In the embodiment, as described above, the base region 210 can be attached to the entire lower surface of the battery cell 100.

[0066] The first point area 220 and the first fixed area 240 can cover the side surface of the battery cell 100. Figure 4 The left surface of the first fixing region 240 (as shown in the image), and the first point region 220 may also cover a portion of the upper surface of the battery cell 100. The wing 241 of the first fixing region 240 can be bent to attach to the side surface of the battery cell 100 opposite to the side surface of the battery cell 100 on which the lead terminals are formed (e.g., the left surface of the battery cell 100), and the first point region 220 may also cover a portion of the upper surface of the battery cell 100. Figure 5 (See the side surface). The second point area 230 can extend from the first point area 220 to attach to the upper surface of the battery cell 100, and a termination area 250 provided at the end of the second point area 230 can prevent or substantially prevent the exposure of the adhesive.

[0067] The second fixing area 260 can cover the other side surface of the battery cell 100. Figure 4 (right surface of the battery cell 100), and the wing 261 of the second fixing region 260 can be bent to attach to the side surface of the battery cell 100 opposite to the side surface of the battery cell 100 on which the lead wires are formed (right surface of the battery cell 100). Figure 5(See the side surface shown). The third point region 270 may further cover a portion of the upper surface of the battery cell 100. A termination region 280 provided at the end of the third point region 270 may prevent or substantially prevent exposure of the adhesive.

[0068] As described above, in the secondary battery 10 according to the embodiment, the cover strip 200 can be bonded to a portion of the lower surface, side surface, and upper surface of the battery cell 100, and the second point area 220 and the third point area 270 of the cover strip 200 covering the upper surface of the battery cell can have relatively low adhesive strength, thereby preventing or substantially preventing the adhesive from being exposed from the upper surface of the battery cell 100.

[0069] In this embodiment, no adhesive is applied to the termination regions 250 and 280 formed at the ends of the second point region 230 and the third point region 270, and the adhesive of the second point region 230 and the third point region 270 is prevented or substantially prevented from being exposed.

[0070] In one or more embodiments, termination regions 250 and 280 can be manufactured in the form of a dam by increasing the thickness of the base material of the strip, thereby preventing or substantially preventing the adhesive of the second point region 230 and the third point region 270 from moving and thus being exposed. In embodiments, termination regions 250 and 280 can be configured to directly contact the upper surface of the battery cell 100 (i.e., the upper surface of the pouch 130), thereby preventing or substantially preventing the exposure of the adhesive.

[0071] As is apparent from the above description, an embodiment may provide a secondary battery configured such that a cover strip adheres to a portion of the lower surface, side surface, and upper surface of the battery cell, such that the second and third point areas of the cover strip covering the upper surface of the battery cell have relatively low adhesive strength, thereby preventing or substantially preventing the adhesive from being exposed from the upper surface of the battery cell.

[0072] In some implementations, termination areas where no adhesive is applied can be formed at the ends of the second and third point areas, thus preventing or substantially preventing the adhesive in the second and third point areas from being exposed.

[0073] In some implementations, the termination zone can be made in the form of a dam by increasing the thickness of the base material of the strip, thereby preventing or substantially preventing the adhesive in the second and third point zones from moving and thus being exposed.

[0074] However, the aspects and effects of this disclosure are not limited to those described above, and other unmentioned technical aspects and effects will be apparent to those skilled in the art based on the above description of some exemplary embodiments.

[0075] Although this disclosure has been described above with reference to a limited number of exemplary embodiments and accompanying drawings, this disclosure is not limited thereto, and it should be understood that various changes and modifications can be made by those skilled in the art within the spirit and scope of this disclosure and the appended claims and their equivalents.

[0076] This application claims priority and benefit from Korean Patent Application No. 10-2023-0192791, filed on December 27, 2023, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference.

Claims

1. A secondary battery, characterized in that, include: Electrode assembly; A bag containing the electrode assembly; as well as A cover strap is attached to the bag to at least partially cover at least two surfaces of the bag. The cap tape includes a fixing area attached to a first surface of the bag, a dotted area attached to a second surface of the bag, and an adhesive on the fixing area and the dotted area. The adhesives described therein have different adhesive strengths.

2. The secondary battery according to claim 1, characterized in that, The fixing area of ​​the cover strap covers the side surface of the bag, and The dotted area of ​​the cover strip covers at least a portion of the upper surface of the bag.

3. The secondary battery according to claim 2, characterized in that, The adhesive on the dotted area has a weaker adhesive force than the adhesive on the fixed area.

4. The secondary battery according to claim 1, characterized in that, The cover tape includes a base area that is attached to the lower surface of the bag and has a first adhesive force.

5. The secondary battery according to claim 4, characterized in that, The cover strip includes: The first point region extends from the side surface of the base region and has a second adhesive force; The second point region is located on the edge of a portion of the first point region and has the first adhesive force; and The first fixed area is located on the edge of the second point area and has a third adhesive force.

6. The secondary battery according to claim 5, characterized in that, The second adhesive force is less than the first adhesive force.

7. The secondary battery according to claim 5, characterized in that, The third adhesive force is greater than the first adhesive force.

8. The secondary battery according to claim 5, characterized in that, The first adhesive force is 0.20 to 0.50 kgf / 25 mm.

9. The secondary battery according to claim 5, characterized in that, The second adhesive force is 0.05 to 0.25 kgf / 25 mm.

10. The secondary battery according to claim 5, characterized in that, The third adhesive force is 1.10 to 1.40 kgf / 25 mm.

11. The secondary battery according to claim 5, characterized in that, The cover strip also includes a termination area at the end of the first fixing area or the third point area, and no adhesive is applied to the termination area.

12. The secondary battery according to claim 11, characterized in that, The termination area is located at the outermost edge of the first fixed area or the third point area.

13. The secondary battery according to claim 11, characterized in that, The termination region has a thickness different from that of the base material of the cover strip.

14. The secondary battery according to claim 11, characterized in that, The termination area is thicker than the base material of the cover strip and contacts the upper surface of the bag.

15. The secondary battery according to claim 4, characterized in that, The cover strip also includes: A second fixing region extends from the opposite side surface of the base region and has a third adhesive force; and The third point area extends along the outer side of the second fixing area and has a second adhesive force.

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