In order to reduce the duration of the electrolyte filling step, Solvay proposes a new concept of separator embedding itself Li salt thanks to a Li salt rich film coated on (Patent Solvay).

The objective of the present study was to quantify the impact (benefits and drawbacks) of a Li salt containing PVdF based film deposited by coating onto a conventional polyolefin based separator. The thin coated layer is composed of Solef® PVdF containing LiTFSI salt in appropriate amount. The separator selected for the study was the Celgard® 2320.

After having developed the method for manufacturing such a coated separator, electrical evaluations were conducted in representative intermediate capacity-level Li-ion cells, trials with pilot coating machines were also performed to demonstrate the feasibility of coating a separator at industrial level and the impact of the storage were also studied.