Interface Structure Design And Stabilization Mechanism Between Lithium Anode And Electrolyte

Metal lithium has shown the significant potential as the anode in a battery because of the low density,the highest specific capacity(3860 mAh cm^-2)and the most negative electrode potential?-3.04 V vs H₂|H⁺?.However,the unstability between lithium anode and the electrolyte bas been one of the major obstacles.A passivation layer will form on the surface of lithium anode in the organic liquid electrolyte,which can result in nonuniform lithium deposites with dendtrite produce.Even though the inorganic solid electrolyte can enhance the safety margin,the solid-solid interface between anode and solid state electrolyte is poor contact indicating huge interface resistance.Hence,this article firstly make a detailed analysis and discussion about the machanism of interface stability between anode and liquid/solid electrolyte,and then construct the new interfacial structure to improve the interface stability and good performance.Three-dimensional current collector?TDCC?was fabricated based on the porous metal copper by rolling.The results of lithium deposites morphology confirm that the TDCC with appropriate pore size contributes to the uniform lithium deposits in the porous structure with lithium dendtrite suppression.The influence of OPVP@InCl₃ interlayer and polymer for facilicating the homogeneous lithium deposite and inhibiting the dendrite growth has been investigated.The results show that the porous polymer interlayer can reduce the regional current density and the indium chloride can in-situ react with lithium to produce an artificial protect layer demonstrating low nucleation barrier and enhanced ions conductivity.The lithium-indium alloy interface layer on lithium anode was got by a spontaneous process,which promotes the interface stability by alloy process during cycling.After assembled into a full cell when paired with LiFePO₄ cathode,the discharge capacity dispalyed an excellent retainment,98%,after 120 cycles.The garnet solid state electrolyte?SSE?with a high ionc conductivity of 2.2×10^-44 S cm^-2 was synthesized by high temperature solid state method.The physical contact between lithium anode and SSE was characterized before/after ionic liquid modifying.The result indicates that a significant decrease of interface resistance,from 3540?cm²to 39?cm²,was achieved.Graphite coating layer on the garnet type SSE was developed by a facile and scale spraying method,which shows an regulated thicknss,smooth surface and robust contact with the substrate.Lithium-graphite alloy anode on the SSE can be in-situ obtained by a thermal process.The results indicate that graphite coating creat the wettability between the metal lithium and SSE with alloy reaction.Due to the novel flake structure of graphite,the interface between this alloy anode and the garnet SSE endure a large volume change of 4.9?m cm^-2 with a high rate and high capacity performing.