| The rapid development of electric vehicle and grid energy storage requires the researchers to exploit rechargeable lithium batteries with high energy density.Li-O2 batteries and solid-statelithiumbatteries have intrigued great interest due to the high theoretical energy density.However,the organic Li-O2 batteries and metallic lithium batteries are still facing some crucial challenges,such as inflammability of the liquid organic electrolytes and easy formation of lithium dendrite.Using?quasi?solid state electrolytes with high conductivity and low interfacial resistance is an ideal strategy to solve this problem.In this work,we designed several polymer/ceramic quasi-solid-state composite electrolytes?QSSE?for quasi-solid-state Li-O2 batteries and lithium batteries.The results are as follows:?1?The sulfide electrolyte Li9.54Si1.74P1.44S11.7Cl0.3 was synthesized by ball milling and solvent method,which exhibits high room-temperature lithium-ion conductivity(1.38×10-3 Scm-1).A quasi-solid-state Li-O2 battery was designed with the Li9.54Si1.74P1.44S11.7Cl0.3/ionic liquid electrolyte.The first discharge capacity was 1049 mAhg-1 at 60 ?.Various QSSEs were prepared via in-situ polymerization by using different monomers with addition of LATP,and by changing polymerization and testing temperature.The Quasi-solid-state lithium battery using QSSE with PTETA monomer,LATP additive and liquid electrolytes shows good electrochemical performance.The discharge specific capacity is as high as 165 mAhg-1.?2?Composite electrolytes were designed by one-pot method,which includes four components,polymer solid electrolyte matrix,ceramic electrolyte additive,lithium salt and plasticizer.The QSSE shows excellent flexibility and suitable ionic conductivity.The Li-O2 battery assembled with the QSSE shows good performance,which maintains a stable cycling up to 196 cycles at 400 mAg-1 with the capacity limited at 1000 mAhg-1.In a full charge/discharge mode at 400 mAg-1,the battery can be cycled for 50 cycles with a capacity over 1000 mAhg-1.A simple soft-pack Li-O2 battery with QSSE was also prepared.It reveals that the fluoride containing-CF3 group in situ formed from the decomposition of PMIMTFSI protects the Li anode,bringing about long cycling life of Li-O2 batteries. |
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