As the output voltage of a pure EVS power battery packcan reach 200V or more, it is essential to ensure that the battery box is properly sealed and. 2.1 Design of the battery box sealing surface The design of the battery pack sealing surface also plays a crucial role in sealing performance. Its design needs to be needs to be aligned with the box structure and sealing ring. 3.1 Air tightness test The main method for airtightness testing for EVS batteriesis to use a gas pressurization system, connect the product to the airtightness tester by using a quick connector,.