Electrochemical properties of nickel-precipitated pyrite as cathode active material for lithium/pyrite cell
By Choi, Y.J.; Kim, N.W.; Kim, K.W.; Cho, K.K.; Cho, G.B.; Ahn, H.J.; Ahn, J.H.; Ryu, K.S. & Gu, H.B.
Published in Journal of Alloys and Compounds
2009
Abstract
The effects of nickel precipitation and the cut-off voltage on the electrochemical properties of a pyrite cathode were investigated by using an electroless nickel-plating method. After nickel precipitation, some nickel particles that were precipitated on the surface of pyrite accumulated between the pyrite powder particles. In the voltage range of 0.4–3.2 V, a cell with nickel-precipitated pyrite exhibited a rapid decrease in discharge capacity and poor columbic efficiency. On the other hand, in the voltage range of 0.8–2.4 V, the cell showed an improved cycle life property and good coulombic efficiency because irreversible reactions below 0.8 V and sulfur oxidation above 2.4 V were suppressed by controlling the cut-off potential and the internal resistance was decreased by nickel precipitation.