Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Electrode heat balances of electrochemical cells: Application to water electrolysis

Journal Article · · J. Electrochem. Soc.; (United States)
DOI:https://doi.org/10.1149/1.2115348· OSTI ID:6017536

Irreversible thermodynamics has been used to describe electrode heat balances of electrochemical cells. The specific example of electrolysis of water in molten sodium hydroxide is chosen for the purpose of illustration. Experimental data are presented for this system. The importance of a distinction between time and chargedependent changes in entropy is pointed out. Only changes of the last type contribute to cell EMF's. The relation between EMF of thermocells, the temperature coefficient of an isothermal cell, and the electrode heat balances are discussed particularly. Results show a reasonably good agreement between theoretical predictions and experimental observations. With partial pressures of hydrogen and water vapor in the cathodic compartment of 0.8 and 0.2 atm, respectively, 63 kJ is evolved, and with partial pressures of oxygen and water vapor in the anodic compartment of 0.8 and 0.2 atm, respectively, 72 kJ is absorbed during the passage of 1F of current at 623 K.

Research Organization:
Department of Nuclear Engineering, Faculty of Engineering, Kyoto University, Sakyo-ku, Kyoto
OSTI ID:
6017536
Journal Information:
J. Electrochem. Soc.; (United States), Journal Name: J. Electrochem. Soc.; (United States) Vol. 131:11; ISSN JESOA
Country of Publication:
United States
Language:
English