Sulfide solid electrolytes(S-SEs)are widely preferred for their high ionic conductivity and processability.However,the further development of S-SEs is hindered by the excessive price of its critical raw materials of L...Sulfide solid electrolytes(S-SEs)are widely preferred for their high ionic conductivity and processability.However,the further development of S-SEs is hindered by the excessive price of its critical raw materials of Li_(2)S.Herein,a low-cost and environmentally friendly method is proposed to synthesize Li_(2)S by the carbothermal reduction reaction of Li_(2)SO_(4)in one step,and the effects of various factors are also discussed.As a result,a purity of 99.67%is obtained over the self-prepared Li_(2)S.More importantly,the cost of the self-prepared Li_(2)S is only about 50$/kg,which is significantly lower than that of the commercial counterpart(10000−15000 dollar/kg).Moreover,the ionic conductivity of Li_(5.5)PS_(4.5)Cl_(1.5)prepared using self-prepared Li_(2)S as raw materials is 4.19 mS/cm at room temperature,which is a little higher than that of Li_(5.5)PS_(4.5)Cl_(1.5)using commercial Li_(2)S(4.05 mS/cm).And the all-solid-state lithium batteries(ASSLBs)with the as-prepared electrolytes could maintain a discharge capacity of 109.9 mA·h/g with an average coulombic efficiency(CE)of 98%after 100 cycles at 0.2 C,which is equivalent to that using commercial Li_(2)S,demonstrating that the preparation strategy of Li_(2)S proposed in this work is feasible.展开更多
基金Project(52374407)supported by the National Natural Science Foundation of China。
文摘Sulfide solid electrolytes(S-SEs)are widely preferred for their high ionic conductivity and processability.However,the further development of S-SEs is hindered by the excessive price of its critical raw materials of Li_(2)S.Herein,a low-cost and environmentally friendly method is proposed to synthesize Li_(2)S by the carbothermal reduction reaction of Li_(2)SO_(4)in one step,and the effects of various factors are also discussed.As a result,a purity of 99.67%is obtained over the self-prepared Li_(2)S.More importantly,the cost of the self-prepared Li_(2)S is only about 50$/kg,which is significantly lower than that of the commercial counterpart(10000−15000 dollar/kg).Moreover,the ionic conductivity of Li_(5.5)PS_(4.5)Cl_(1.5)prepared using self-prepared Li_(2)S as raw materials is 4.19 mS/cm at room temperature,which is a little higher than that of Li_(5.5)PS_(4.5)Cl_(1.5)using commercial Li_(2)S(4.05 mS/cm).And the all-solid-state lithium batteries(ASSLBs)with the as-prepared electrolytes could maintain a discharge capacity of 109.9 mA·h/g with an average coulombic efficiency(CE)of 98%after 100 cycles at 0.2 C,which is equivalent to that using commercial Li_(2)S,demonstrating that the preparation strategy of Li_(2)S proposed in this work is feasible.
