Electrochemical characteristics of Na/FeS2 battery by mechanical alloying

To develop the battery with low cost and high energy density, Na/FeS2 battery was prepared using FeS2 powder synthesized by mechanical alloying. With increasing the milling time from 20 to 60 h, the size of FeS2 powder decreased from 0.85 to 0.55 μm. The discharge capacity of Na/FeS2 battery depended on the synthesizing condition of FeS2 powder. The FeS2 electrode prepared by 30 h milling showed the highest discharge capacity of 447 mAh g−1-FeS2. The discharge capacity decreased continuously by repeated charge–discharge cycling, and remained 70 mAh g−1-FeS2 after 50th cycles. The Na/FeS2 cell could be used as a rechargeable battery at room temperature.