Electrolytic capacitor conductivity of metals. In 1991 Panasonic came on the market with its "SP-Cap", called polymer aluminum electrolytic capacitors. These aluminum electrolytic capacitors with polymer electrolytes reached very low ESR values directly comparable to ceramic multilayer capacitors (MLCCs). They were still less expensive than tantalum capacitors and with their flat design for laptops and cell phones competed with tantalum chip capacitors as well. Tantalum electrolytic capacitors with PPy polymer electrolyte cathode followed three years later. In 1993 NEC introduced its SMD polymer tantalum electrolytic capacitors, called "NeoCap". In 1997 Sanyo followed with the "POSCAP" polymer tantalum chips. A new conductive polymer
Plasma electrolytic oxidation consisting of the wall of the bath itself. Potentials of over 200 V are applied between these two electrodes. These may be continuous or pulsed direct current (DC) (in which case the part is simply an anode in DC operation), or alternating pulses (alternating current or "pulsed bi-polar" operation) where the stainless steel counter electrode might just be earthed. One of the remarkable features of plasma electrolyte coatings is the presence of micro pores and cracks on the coating surface. Plasma electrolytic oxide coatings are generally recognized for high hardness, wear resistance, and corrosion resistance. However, the coating properties are