A facile and scalable method is proposed to prepare microscale Li2S-C composite from Li2SO4 through carbon-thermal reduction, followed by a carbon coating process. Multi-solvent recrystallization was utilized to reduce the particle size of Li2SO4 to 2 μm. This fine-grain Li2SO4 helps to shorten the particle size of reduction product from 10 μm to 3 μm. Using fine Li2SO4 also brings the benefit of greatly reducing the over potential during the initial charge process and increasing the kinetics for Li2S materials. Finally, the microscale Li2S-C composite prepared from fine Li2SO4 enables a stable capacity of 350 mAh g-1 at 0.2 C, higher than that obtained using a cathode prepared from commercial Li2SO4.
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