Effects of Current Collectors on Electrochemical Performance of FeS2 for Li-ion Battery

The effects of current collectors on the electrochemical performance of FeS2 electrode have been investigated by applying three types of current collectors, including an Al foil, a Cu foil and a Ni foil. The results show that Ni current collector can greatly improve the discharge capacity and cycle ability of FeS2 electrode compared to the Al current collector. Cyclic voltammetry and electrochemical impedance spectroscopy also show that the electrodes on the Ni foil show much smaller polarization and lower impedance. Although Cu foil is utilized as anode current collector in the conventional lithium ion batteries, it can react with FeS2 during the charge/discharge process, so Cu current collector may also be unsuitable to other metallic sulfide electrode except CuS electrode for lithium ion batteries. These results mean that adopting Ni foil as the current collector is more suitable for metallic sulfide electrodes.