Solvay plans to expand capacity for its Solef polyvinylidene fluoride line at its Tavaux, France, site by 50%. The company expects to complete the $36 million project next year. Solef is used in oil and gas extraction, binders for lithium-ion batteries, photovoltaic power, semiconductor manufacturing, and water purification membranes. Solvay estimates the market for the polymer has been growing at a 10% annual rate for the past five years. The company expanded capacity by 30% in 2009.