Patent ID: 7914925

Claim:
A method of producing a sheet-shaped secondary battery, comprising the steps of: sandwiching a sheet-shaped separator formed of a porous stretched sheet by a sheet-shaped electrode pair, the separator having a maximum expanding direction directed in a maximum stretching direction of the porous stretched sheet due to penetration of an electrolytic solution; inserting the separator sandwiched by the electrode pair into a sheet-shaped outer wrapper having an opened portion; injecting the electrolytic solution into the sheet-shaped outer wrapper; holding the sheet-shaped outer wrapper in a state where the maximum expanding direction of the separator is substantially vertical along the direction of gravity so that the electrolytic solution upwardly penetrates from a lower part of the separator into the separator without fixing motion of the separator in the maximum expanding direction and with the maximum expanding direction of the separator and a penetrating direction of the electrolytic solution being substantially parallel to each other; and sealing the opened portion into a tightly sealed state.