Helium injection method for soft package lithium battery

The invention discloses a method for injecting helium into a soft package lithium battery, which comprises the following steps: placing a cell structure to be filled with helium into a box body, and sealing the box body; after air in the packaging bag of the battery cell structure is emptied, helium is injected into the packaging bag; and packaging the packaging bag injected with the helium gas, completely pumping the helium gas outside the packaging line and the helium gas on the outer surface of the packaging bag, and taking out the cell structure injected with the helium gas from the box body to complete helium gas injection. According to the helium injection method for the soft lithium battery provided by the invention, helium can be hermetically injected into the soft lithium battery, and helium can be effectively prevented from being remained on the outer surface of the battery cell after the whole helium injection process is finished. After the soft package lithium battery is filled with helium, the so