Electrochemical behavior of nonporous Ni/NiCl{sub 2} electrodes in chloroaluminate melts

Journal Article · Tue Feb 01 04:00:00 EST 2000 · Journal of the Electrochemical Society

DOI:https://doi.org/10.1149/1.1393224· OSTI ID:20023338

Prakash, J; Redey, L; Vissers, D R

The electrochemical behavior of nonporous Ni/NiCl{sub 2} electrodes was studied using an Al/Na[AlCl{sub 4}]-NaCl/NiCl{sub 2}/Ni cell in which the capacities of the cell were limited by the Ni/NiCl{sub 2} electrode. The limiting mechanism of the electrode was found to be associated with formation of NiCl{sub 2} on the surface of the nickel electrode. This phenomenon limits the mass-transfer processes of the nonporous electrode and thus its area capacity density. Based on the results of these investigations, an electrochemical model of the electrode reactions was developed which predicts the performance characteristics of porous Ni/NiCl{sub 2} electrodes for various conditions of operation. Modifying the electrolyte with the NaBr, NaI, and sulfur additives was found to produce higher nickel utilization and lower impedance values due to doping effects, which is believed to open up the lattice for better mass transport. Solubility of the nickel chloride in sodium-chloroaluminate melts as a function of temperature and additives was also determined. The solubility measurements indicated that the solubility of nickel chloride in the chloroaluminate melt is strongly dependent on the operational temperature of the cell and the chemical additives present in the electrolyte. The results of this study clearly indicate the importance of the chemical additives, basicity of the melt, and the lower operating temperature of the Na/NiCl{sub 2} cell for improved performance and cycle life.

• Research Organization: Illinois Inst. of Tech., Chicago, IL (US)
• Sponsoring Organization: US Department of Energy
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 20023338
• Journal Information: Journal of the Electrochemical Society, Journal Name: Journal of the Electrochemical Society Journal Issue: 2 Vol. 147; ISSN 0013-4651; ISSN JESOAN
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
33 ADVANCED PROPULSION SYSTEMS
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ALUMINIUM CHLORIDES
ELECTRIC-POWERED VEHICLES
ELECTROCHEMISTRY
ELECTRODES
METAL-NONMETAL BATTERIES
NICKEL CHLORIDES
SODIUM
SOLUBILITY
TEMPERATURE DEPENDENCE