Fig. 5: Electrochemical performances.

a CV curves of Li₂FeS_2-xF_x for \(x\) = 0 and 0.3 electrodes during first and second cycles. b GCD curves of Li₂FeS_2−xF_x for \(x\) = 0 and 0.3 at a rate of C/5. c, d Comparison of long-term cycling performance at C/5 and rate capability test for the pristine and optimized electrodes, respectively.