MATHEMATICAL MODELING OF LITHIUM(ALLOY), IRON SULFIDE CELLS AND THE ELECTROCHEMICAL PRECIPITATION OF NICKEL HYDROXIDE.

摘要

Part A. Computer programs simulating the behavior of LiAl/FeS(,2) and Li(Si)/FeS(,2) high temperature molten salt cells have been developed. The models predict the cell voltage, temperature, and heat-generation rate during cell operation. Position-dependent behavior such as reaction-rates and concentrations within the cell are also calculated. The models predict operational characteristics and determine the influence of changes in design parameters on the performance of the cells. The effects of state-of-discharge, initial electrolyte composition, temperature, and discharge current density on cell behavior are investigated. Factors that can limit a cell during operation are identified. The cell discharge behavior is compared with available experimental data. The models clarify our understanding of the battery systems and help guide experimental research.; Part B. The objective of this research is to develop a fundamental understanding of the precipitation of nickel hydroxide from acidic nickel nitrate solutions. This chemical process occurs in the fabrication of nickel battery electrodes. A mathematical model that simulates the formation and growth of a nickel hydroxide film on a rotating disk electrode has been developed and used to study the system. Experimental investigations of the system are also conducted with a rotating disk electrode apparatus. A mechanism for the nitrate-reduction reaction has been proposed. Experimental studies are conducted, along with theoretical efforts, in order to verify the proposed reaction sequence.