Preparation of Anion-Shielding Covalent Organic Frameworks Based Composite Interlayer for Lithium Battery and Its Effect on Electrochemical Performance
Currently,the implementation of a strategy that restricts the migration of anions stands as an effective approach for attaining dendrite-free and stable Li-metal anodes.In this investigation,anion-shielded composite interlayers were judiciously designed for the promotion of dendrite-free and high-performance Li-metal anodes.The covalent organic framework TpPa-SO3 Li based mixed matrix interlayer(CMIs)TpPa-SO3Li@PVDF-HFP was fabricated.The negative charged sulfonates of TpPa-SO3Li are conductive to ensuring Li-ion transport and hindering the anion migration,and thus improves the transference number of Li-ion with uniform Li-ion flux,real-izing the uniform Li deposition.As a result,the CMIs-modified Li/Li symmetric batteries are found to prolonged li-fetime of more than 1 900 h without short-circuit failure at a current density of 1 mA·cm-2 with a capacity of 1 mAh·cm-2.When the Li-metal anode coupled with LiFePO4 cathode,the assembled full batteries with the CMIs deliver a high capacity of 142.7 mAh·g-1 and 92％of the capacity retention is observed even after 300 cycles at 1 C.
万方数据
维普
