Electrolysis of water a small-scale electrolytic cell. It consists of three joined upright cylinders. The inner cylinder is open at the top to allow the addition of water and the electrolyte. A platinum electrode is placed at the bottom of each of the two side cylinders, connected to the positive and negative terminals of a source of electricity. When current is run through the Hofmann voltameter, gaseous oxygen forms at the anode (positive) and gaseous hydrogen at the cathode (negative). Each gas displaces water and collects at the top of the two outer tubes, where it can be drawn off with a stopcock.
Vanadium redox battery cell electrochemistry within the electrode is poorly known. Electrolytic wetting of carbon electrodes in VRFBs is important for overcoming sources of degradation and applying appropriate operational procedures. Recently, it appears that electrolytic wetting behaviour within the electrode may be influenced by local concentration effects as well as capillary action. Rapid wetting or permeation may also leave behind undissolved gases which could cause electrode degradation. The extremely large capacities possible from vanadium redox batteries make them well suited to use in large power storage applications such as helping to average out the production of highly variable generation sources such as wind