Method and system for replacing electrolyte solution of secondary battery

An electrolyte solution replacement system comprising:

• a secondary battery, the secondary battery comprising:
• an exterior body comprising a first opening, a second opening and a third opening, and
• an electrolyte solution in the exterior body;
• and
• a filter,
• wherein the first opening and the second opening are on an upper surface of the exterior body and the third opening is on a bottom surface of the exterior body which is opposite to the upper surface,
• wherein the third opening is configured to expel the electrolyte solution outside the exterior body by injection of an inert gas into the exterior body through the first opening,
• wherein the filter is configured to perform filtration of the electrolyte solution expelled from the third opening, and
• wherein the first opening is configured to expel the inert gas when the electrolyte solution after the filtration is injected into the exterior body from the second opening.

An electrolyte solution replacement system comprising:

• a secondary battery, the secondary battery comprising:
• an exterior body comprising a first opening, a second opening and a third opening, and
• an electrolyte solution in the exterior body,
• a filter connected to the second opening;
• a server connected to the third opening;
• and
• a pump between the filter and the server,
• wherein the first opening and the second opening are on an upper surface of the exterior body and the third opening is on a bottom surface of the exterior body which is opposite to the upper surface,
• wherein the third opening is configured to expel the electrolyte solution from the exterior body by injection of an inert gas into the exterior body through the first opening,
• wherein the electrolyte solution expelled to the server is configured to be passed through the server, the pump and the filter, and
• wherein the first opening is configured to expel the inert gas when the electrolyte solution passed through the filter is injected into the exterior body from the second opening.