Future availability of high-temperature power inverters will advance the market share for highly fuel-efficient, environmentally friendly electric drive vehicles (EDVs). An integral part of vehicle power inverters is the DC buss capacitor, which has a significant influence on inverter lifetime, reliability, cost, and temperature of operation. Funded by the U.S. Department of Energy’s Vehicle Technologies Program, Argonne is developing lead lanthanum zirconium titanate (PLZT)-based film capacitors for vehicular applications. A high-rate aerosol deposition (AD) process is being developed at Argonne to produce PLZT films with desirable properties. The AD process can produce dense films at room temperature; thus making the process amenable for depositing PLZT films on a variety of substrates such as polymer, glass, and metal foils. Recently we demonstrated that a ≈8-μm-thick PLZT film on aluminum-metallized polyimide substrate can be deposited in less than 10 minutes by the AD process. Films deposited by the AD process exhibited dielectric constant of ≈ 80 at 300 V bias, dielectric loss < 2%, mean breakdown voltage of ≈ 1000 V, and temperature-dependent properties suitable for advanced power inverters. Our results show that the AD process has great potential in reducing the manufacturing cost of high-temperature capacitors. Recently we produced ≈ 30 cm long and ≈ 2.5 cm wide PLZT films on aluminum-metallized thin polymer substrates. These PLZT films were wound into capacitors with terminations. The dielectric properties of the long-length PLZT films and the wound capacitors will be presented in this talk.
Work supported by the U.S. Department of Energy, Vehicle Technologies Program, under Contract DE-AC02-06CH11357.