Fast charging Lithium metal battery based on Lewis Acid/Base dual-site solid electrolyte interphase

• A Lewis acid/base dual-site additive (triisopropanolamine cyclic borate , BON) is employed to construct a novel artificial SEI . • The tertiary amine nitrogen atom in BON, serving as the Lewis base site, can regulating the transport of lithium ions ; the boron atom , acting as the Lewis acid site, can anchor the anion to prevent its depletion at the interface. • The innovative SEI layer can greatly boost the fast charging performance and stability of lithium batteries . The LFP full cells exhibit a remarkable capacity retention of 93.7 % at an ultrahigh current density of 10 C, even after undergoing 2000 cycles. The unexpected depletion of anions and the restricted diffusion of Li + on the Li anode lead to uncontrolled dendrite growth in Li metal batteries. Solid electrolyte interphase (SEI) engineering has been proven to be an effective method for solving these issues. Herein, a novel SEI layer with Lewis acid/base dual-site is constructed with triisopropanolamine cyclic borate (BON) and LiTFSI (defined as TFBN) to regulate the transport behavior of anions and Li + . The electron-deficient boron atom in BON can serve as the Lewis acid site, which anchors the anion to prevent its depletion at the interface. Meanwhile, the electron-rich nitrogen atom can serve as the Lewis base site, which accelerates the transport of Li + to facilitate smooth Li deposition. As a result, BON can effectively dissociate lithium salts and regulate the migration behavior of anions and Li + . Using this novel SEI layer, Li||Li symmetric batteries can achieve stable cycling for over 1200 h at 1.0 mA cm − ². Furthermore, the Li||LFP full cells show 93.7 % capacity retention after 2000 cycles at an ultrahigh current of 10 C. Triisopropanolamine cyclic borate (BON) combined with LiTFSI is used to construct a novel artificial SEI (TFBN) to improve anode interface. The tertiary amine nitrogen atom in BON, serving as the Lewis base site, can accelerate the transport of Li + ; the boron atom, acting as the Lewis acid site, can anchor the anion to prevent anion depletion at the interface. With the help of this SEI, TFBN@Li demonstrates impressive fast charging performance at 10 C in LFP full cells.