NOVELTY - The system has an anode and cathode current collecting tabs which are connected to anode and cathode of the lithium ion cell accommodated in an external case (8). A case lid (7) having a current collecting pole (9) is connected hermetically sealed external case (15). The cells are encloses by an initial enclosure made of plastic. The current collecting tabs are extended through the initial enclosure. The current connecting poles made of aluminum is included with positive and negative poles.    USE - Sealing system for lithium-ion battery used in energy storage systems and high power applications such as electric vehicles and hybrid electric vehicles.    ADVANTAGE - The leakage of electrolyte can be prevented owing to the presence of two layers of protection with two hermetic sealings, and the need of using copper as the negative pole is eliminated owing to the avoidance of direct contact of the current collecting pole with the electrolyte. The negative current collecting pole can be made of aluminum or any other less costly materials, rather than copper, due to the initial hermetic sealing. The need for filling electrolyte into the battery after sealing the rigid case is eliminated, and the initial enclosure limits the space requiring electrolyte, so that the amount of electrolyte addition can be minimized. The increase of gas pressure in the final battery can be reduced, since degassing is performed before the initial hermetic sealing is conducted. The damage of electrode stacks can be prevented by gluing, if the final battery is subjected to vibration or other forces. Production yield of the final battery can be increased if cells subjected to the initial hermetic sealing can be examined and tested individually before they are grouped together and placed inside the external case.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for method for sealing lithium-ion battery.    DESCRIPTION OF DRAWING(S) - The drawing shows the perspective view of the hermetically sealed initial enclosures.    Case lid (7)    External case (8)    Current collecting pole (9)    Safety vent (10)    Hermatically sealed external case (15)