Galvanostatic configuration

A very interesting application of the classical current interruption technique has been reported by Lorenz and Eichkom [67], who showed that by adopting the galvanostatic configuration it is possible to evaluate the importance of the ohmic drop realistically, point by point, and obtain polarization curves with a trend very close to the ideal one. In fact, it can be experimentally demonstrated that the value of R, is not constant but is influenced by the mass transfer when the current flowing in the electrolytic cell is sufficiently high. In other words, it cannot be excluded a priori that the quantity R, depends on the electrode overvoltage. 

The actual surface area of the lithium electrode was 9.954 cm and the electrolyte solution filled a volume of 2.35 cm. The impedances of newly received and aged cells were measured, and the cells were then discharged galvanostatically at the 100 h rate (37.5 mA) using a Kemitron P-50 potentiostat in a galvanostatic configuration with a CM-2 coulometer. Impedance measurements were made at a series of discharge states. 

The opposite conclusion was reported by Lin et al., who used a three-electrode configuration to study the electrode polarization of the MCMB anode and LiCo02 cathode under galvanostatic conditions. They found that in all cases the polarization at the MCMB anode surface far outweighs that at the cathode to such an extent that the potential profile... 

Electrolyses at sacrificial electrodes allow direct synthesis of metal complexes from bare metal electrodes. Systematic studies have been reported and periodically reviewed.22-24 The sacrificial electrode may either be a cathode (Pb, Sn, Hg), or an anode (metals) which is the most usual configuration. The experiments are generally carried out under galvanostatic conditions (10-30 mA cm-2) and so a reference electrode and a potentiostat are not required. Different types of products have been obtained from the simplest complexes to clusters. 

Figure 5 Reactor cell (a) and electrode configuration (b) for NEMCA studies using the fuel-cell type design G-P Galvanostat-Potentiostat. Reprinted with permission from Elsevier Science Publishers B.V., Amsterdam. ...

R.D. Beach, R.W. Conlan, M.C. Godwin, et al, Towards a Miniature Implantable in Vivo Telemetry Monitoring System Dynamically Configurable as a Potentiostat or Galvanostat for Two- and Three-Electrode Biosensors, IEEE Transactions on Instrumentation and Measurement, vol. 54, no. 1, pp. 61-72, 2005. 

There are a wide number of different cell geometries, electrode configurations, and other process considerations in any electrochemical system, together with different means of imposing power using galvanostatic, potentiostatic, constant... 

Figure 3. Electrode configuration for SEP (a) and for PPR or NEMCA studies (b). The latter can be carried out using the fuel-cell type configuration (c) or the single-pellet type configuration (d). G/P, Galvanostat/potentiostat.

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