Time-dependent energy efficiency losses at nickel cathodes in alkaline water electrolysis systems

Journal Article · Fri Feb 01 04:00:00 EST 1985 · J. Electrochem. Soc.; (United States)

DOI:https://doi.org/10.1149/1.2113831· OSTI ID:6213244

Rommal, H E.G.; Moran, P J

Water electrolysis in alkaline solutions is an important hydrogen production method. One difficult encountered in systems employing nickel electrodes in KOH electrolytes is the continual decrease in operating efficiency with time. The major component of this decrease is the rise in cathodic overpotential at constant cell current. It was found that the kinetic parameters of Tafel slope and exchange current density increase markedly with the decline of efficiency. Four mechanisms have previously been postulated as being responsible for this phenomenon. In the present work, it was found that the loss of efficiency can be completely recovered, and an examination of the recovery mechanism supports the theory of hydrogen absorption's being responsible for the efficiency decline.

• Research Organization: Department of Materials Science and Engineering, The Johns Hopkins University, Baltimore, MD
• OSTI ID: 6213244
• Journal Information: J. Electrochem. Soc.; (United States), Journal Name: J. Electrochem. Soc.; (United States) Vol. 132:2; ISSN JESOA
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
080101* -- Hydrogen-- Production-- Electrolysis
ABSORPTION
ALKALI METAL COMPOUNDS
ALKALINE HYDROLYSIS
CATHODES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CURRENT DENSITY
DECOMPOSITION
EFFICIENCY
ELECTRODES
ELEMENTS
ENERGY EFFICIENCY
ENERGY LOSSES
HYDROGEN
HYDROGEN COMPOUNDS
HYDROGEN PRODUCTION
HYDROLYSIS
HYDROXIDES
KINETICS
LOSSES
LYSIS
METALS
NICKEL
NONMETALS
OXYGEN COMPOUNDS
POTASSIUM COMPOUNDS
POTASSIUM HYDROXIDES
REACTION KINETICS
SOLVOLYSIS
TIME DEPENDENCE
TRANSITION ELEMENTS