Secondary battery having a case including a liquid-phase short-circuit prevention layer
The present invention relates to a secondary battery that is capable of preventing short circuit from occurring when a nail test is performed. Also, the secondary battery includes a case accommodating an electrolyte and an electrode assembly therein, and the case includes an external layer exposed to the outside, an internal layer disposed in the case, and a short-circuit prevention layer provided in a liquid phase between the external layer and the internal layer.
1. A secondary battery comprising:
a case accommodating an electrolyte and an electrode assembly therein,
wherein the case comprises:
an external layer exposed to the outside and made of polyethylene terephthalate (PET);
an internal layer disposed in the case and made of polypropylene (PP);
an oil layer containing an oil provided in a liquid phase between the external layer and the internal layer;
an aluminum layer disposed between the external layer and the oil layer; and
an adhesion layer disposed between the aluminum layer and the external layer and provided as an adhesion member that allows the aluminum layer to adhere to the external layer,
wherein the oil directly contacts the internal layer and the aluminum layer.
2. The secondary battery of claim 1 , wherein the oil comprises an insulation oil.