Pouch case for secondary battery and pouch-type secondary battery comprising the same
View Patent ↗The present disclosure relates to a pouch case for a secondary battery, and a secondary battery comprising the same, and in particular, to a pouch case for a secondary battery fabricated by laminating an inner resin layer, a middle resin layer and an outer resin layer, wherein the inner resin layer comprises a polyolefin-based resin and a thermosetting moisture absorber, and a secondary battery comprising the same.
1. A pouch case for a secondary battery fabricated by laminating an inner resin layer, a middle resin layer and an outer resin layer,
wherein the inner resin layer comprises a polyolefin-based resin and a thermosetting moisture absorber,
wherein the thermosetting moisture absorber comprises at least one selected from the group consisting of acrylate-based copolymers, ethylene-maleic anhydride copolymers, carboxymethylcellulose and polyethylene oxide, and
wherein the thermosetting moisture absorber is prepared to powder having a particle diameter of from 1 μm to 5 μm by grinding.
2. The pouch case for the secondary battery of claim 1 , wherein the polyolefin-based resin comprises at least one selected from the group consisting of oriented or casted polypropylene copolymers, polyethylene copolymers, ethylene-propylene copolymers, and copolymers of polypropylene and acrylic acid.
3. The pouch case for the secondary battery of claim 1 , wherein the thermosetting moisture absorber is comprised in an amount of from 1 wt % to 5 wt % based on the total weight of the polyolefin-based resin.
4. The pouch case for the secondary battery of claim 1 , wherein the thermosetting moisture absorber is dispersed in the polyolefin-based resin.
5. The pouch case for the secondary battery of claim 1 , wherein the inner resin layer is prepared by grinding the thermosetting moisture absorber to prepare thermosetting moisture absorber powder; dispersing the thermosetting moisture absorber powder into a polyolefin-based resin solution; and extruding the thermosetting moisture absorber powder-dispersed polyolefin-based resin solution to prepare a film.
6. The pouch case for the secondary battery of claim 1 , wherein a thickness of the inner resin layer is from 20 μm to 100 μm.
7. The pouch case for the secondary battery of claim 1 , wherein the middle resin layer comprises a cyclic olefin-based resin.
8. The pouch case for the secondary battery of claim 1 , wherein a thickness of the middle resin layer is from 60 μm to 100 μm.
9. The pouch case for the secondary battery of claim 1 , wherein the outer resin layer comprises at least one selected from the group consisting of polyethylene, polypropylene, polyethylene terephthalate, nylon, low-density polyethylene (LDPE), high-density polyethylene (HDPE) and linear low-density polyethylene (LLDPE).
10. The pouch case for the secondary battery of claim 1 , wherein a thickness of the outer resin layer is from 10 μm to 100 μm.
11. A pouch-type secondary battery comprising: an electrode assembly; and the pouch case for the secondary battery of claim 1 accommodating the electrode assembly.
12. The pouch-type secondary battery of claim 11 , which is used as a unit battery of a battery module for a power supply of medium and large sized devices.