Cathode is positive and therefore would be expected to repel the positively charged cations; this is due to electrode potential relative to the electrolyte solution being different for the anode and cathode metal/electrolyte systems in a galvanic cell). The cathodic current, in electrochemistry, is the flow of electrons from the cathode interface to a species in solution. The anodic current is the flow of electrons into the anode from a species in solution. In an electrolytic cell, the cathode is where the negative polarity is applied to drive the cell. Common results of reduction at the cathode are hydrogen gas or
Aluminum electrolytic capacitor for better self-healing property of the oxide layer, so that the capacitors have the advantages of both low ESR and low leakage current. The basic material of the anode for aluminum electrolytic capacitors is a foil with a thickness of ~ 20–100 µm made of aluminum with a high purity of at least 99.99%. This is etched (roughened) in an electrochemical process to increase the effective electrode surface. By etching the surface of the anode, depending on the required rated voltage, the surface area can be increased by a factor of approximately 200 with respect to a smooth surface. After