Swelling tape for filling gap
View Patent ↗A swelling tape for filling a gap, a method of manufacturing the swelling tape for filling a gap, a method of filling a gap, an electrode assembly and a secondary battery are provided. For example, the swelling tape can be applied inside a gap in which a fluid exists so as to fill the gap by becoming a 3D form, and can be useful at anchoring a subject in which the gap is formed, as necessary.
1. A secondary battery comprising:
an electrode assembly comprising a swelling tape attached thereto;
a can configured to accommodate the electrode assembly; and
an electrolyte coming in contact with the swelling tape of the electrode assembly inside the can,
wherein the swelling tape comprises:
a substrate layer having a property of deforming in a longitudinal direction when coming in contact with a fluid, wherein the substrate layer contains a urethane bond, an ester bond or an ether bond, or includes a cellulose ester compound; and
a pressure-sensitive adhesive layer that is formed on one surface of the substrate layer in a direction parallel to the longitudinal direction of the substrate layer, wherein the pressure-sensitive adhesive layer includes at least two pressure-sensitive adhesive regions and at least one non-pressure-sensitive adhesive region disposed between the at least two pressure-sensitive adhesive regions,
wherein the pressure-sensitive adhesive region and the non-pressure-sensitive adhesive region are formed on a surface of the pressure-sensitive adhesive layer opposite to the substrate layer, and the non-pressure-sensitive adhesive region is embedded in the pressure-sensitive adhesive layer.
2. The secondary battery of claim 1 , wherein the swelling tape has a three-dimensional (3D) structure having a height of 0.001 mm to 2.0 mm in a direction perpendicular to the longitudinal direction when coming in contact with the fluid.
3. The secondary battery of claim 1 , wherein the substrate layer has a modification rate of 10% or more in the longitudinal direction according to the following Equation 1:
Modification rate in longitudinal direction=( L 2 −L 1 )/ L 1 ×100 Equation 1
wherein L 1 represents an initial length of the substrate layer before the substrate layer comes in contact with a fluid, and L 2 represents a length of the substrate layer measured after the substrate layer comes in contact with the fluid at room temperature or 60° C. for 24 hours.
4. The secondary battery of claim 1 , wherein a ratio of an area of the pressure-sensitive adhesive region to the entire area of a surface of the pressure-sensitive adhesive layer is in a range of 5% to 95%.
5. The secondary battery of claim 1 , wherein the pressure-sensitive adhesive layer is a single-layered pressure-sensitive adhesive layer.
6. The secondary battery of claim 5 , wherein a distance between the pressure-sensitive adhesive regions is in a range of 0.1 mm to 10 mm.
7. The secondary battery of claim 1 , wherein the pressure-sensitive adhesive region or the non-pressure-sensitive adhesive region is disposed to form a striped pattern; or the pressure-sensitive adhesive region and the non-pressure-sensitive adhesive region are formed in a sea island pattern.
8. The secondary battery of claim 1 , the pressure-sensitive adhesive layer comprises a non-pressure-sensitive adhesive material that forms the non-pressure-sensitive adhesive region by partly masking the pressure-sensitive adhesive layer.
9. The secondary battery of claim 1 , wherein the pressure-sensitive adhesive layer has a peel strength at room temperature of 100 gf/25 mm or more, as measured at a peel angle of 180° and a peel rate of 5 mm/sec with respect to either an electrode assembly or glass plate having the gap formed therein.
10. The secondary battery of claim 1 , wherein the pressure-sensitive adhesive layer includes an acrylic pressure-sensitive adhesive, a urethane pressure-sensitive adhesive, an epoxy pressure-sensitive adhesive, a silicon pressure-sensitive adhesive or a rubber pressure-sensitive adhesive.
11. The secondary battery of claim 1 , wherein the swelling tape has a 3D structure formed by means of the electrolyte, and functions to anchor the electrode assembly in the can.
12. The secondary battery of claim 1 , wherein the at least one non-pressure-sensitive adhesive region forms a striped pattern.
13. The secondary battery of claim 1 , wherein the at least two pressure-sensitive adhesive regions and the at least one non-pressure-sensitive adhesive region form a sea island pattern.