| Lithium metal batteries have been extensively regarded as the most promising next-generation rechargeable energy storage devices due to their high energy density.However,conventional lithium metal batteries using liquid organic electrolytes exhibit severe security risks such as electrolyte leakage,burning,or even explosion.Solid electrolytes have attracted increasing attentions as they can solve the safety issue resulted from liquid electrolytes.But their low conductivity,poor mechanical stability and high interfacial impedance with electrode restrict the practical application of all-solid-state lithium metal batteries.In this paper,the integrated structure of all-solid-state lithium batteries with solid composite electrolyte was designed and the interface between ceramic/electrode with low resistance and excellent stability was constructed.First,all-solid-state ceramic/polymer composite electrolytes were prepared by compositingthepolyethyleneoxide（PEO）andlithium bis（trifluoromethylsulphonyl）imide（LITFSI）with Li7La3Zr2O12（LLZO）microparticles and nanowires.Their effects on lithium dendrite growth were investigated.The LLZO nanowires uniformly distributed in PLLN can increase the ionic conductivity and mechanical strength of the composite electrolyte efficiently,which induces the uniform deposition of lithium metal,thereby suppressing the lithium dendrite growth.The Li symmetric cells using PLLN can stably cycle for 1000 h without short circuit at 60°C.Then a low resistance-integrated all-solid-state battery is designed with excellent electrochemical performance that applies PEO/LITFSI as both binder of cathode and matrix of composite electrolyte embedded with LLZO nanowires（PLLN）.The PEO in cathode and PLLN are fused at high temperature to form an integrated all-solid-state battery structure,which effectively strengthens the interface compatibility and stability between cathode and PLLN to guarantee efficient ion transportation during long cycling.The integrated Li Fe PO4/PLLN/Li batteries show excellent cycling stability at both 60 and45°C.By using PLLN as solid electrolyte as well as binder in the cathode,the integration degree of solid batteries were also increased.At 60°C,the coulombic efficiency and the cycle performance of the all-solid-state Li Fe PO4/PLLN/Li cell were improved.Due to the nature of polymer electrolytes,the batteries with composite solid electrolytes are difficult to operate at room temperature.In order to design a solid-state battery working at room temperature,the surface of the dense ceramic Li6.4La3Zr1.4Ta0.6O12（LLZTO）was modified by magnetron sputtering of Zn and the alloy was formed by melting Li to reduce the interface impedance.The Li Co O2/LLZTO-Zn/Li quasi-solid state battery with a small amount of electrolyte exhibits good performance at room temperature.Finally,plastic crystal succinonitrile（SN）and LITFSI with LLZO nanowires were used to reduce the resistance between the cathode and the ceramic electrolyte,in which the LLZO nanowires improve the mechanical properties and stability.Eventually all solid state batteries were successfully prepared. |
