Magnetron sputtering deposition of TiO2 particles on polypropylene separators for lithium-ion batteries

Magnetron sputtering deposition (MSD) of TiO 2 is applied on a porous polypropylene (PP) separator for lithium ion batteries. The surface morphology, contact angles, thermal properties, and electrolyte uptake of the modified separators are characterized and the electrochemical performances such as ionic conductivity, cycle performance, and high rate discharge capacity are investigated. The TiO 2 MSD-coated separators present suppressed thermal shrinkage which may lead to improved safety of the batteries, and show improvement in wettability with polar electrolytes and cell performance as compared to the bare PP separator. After MSD of TiO 2 , the modified separators presented suppressed thermal shrinkage and improved wettability to electrolytes, resulting in better cell performances.